Brachytherapy apparatus and methods of using same

Apparatus, systems and methods for delivering brachytherapy to a target tissue region of a human or other mammalian body. In some embodiments, a flexible brachytherapy device is implanted that includes a therapy delivery portion having one or more radioactive sources securely retained thereto, and a tail portion extending from the therapy delivery portion. Once implanted, the tail portion may extend outside the body, where it may be folded and secured flat against the skin. The device may be removed at therapy completion. Other embodiments of the invention are directed to systems and methods for delivering brachytherapy devices to the body.

TECHNICAL FIELD

The invention pertains generally to medical treatment and, more specifically, to apparatus, methods, and systems for providing brachytherapy to a human or other mammalian body.

BACKGROUND

Brachytherapy is a type of radiation therapy used to treat malignant tumors such as cancer of the breast or prostate. In general, brachytherapy involves the positioning of a radiation source directly into target tissue, which may typically include the tumor and/or surrounding tissue that may contain potentially cancerous cells (such as a cavity or void created by removal of the tumor).

Brachytherapy is often divided into two categories: high dose rate (HDR); and low dose rate (LDR). In HDR brachytherapy, a high activity radiation source is placed into the target tissue, often via a previously implanted catheter, for a short period of time, e.g., seconds to a few minutes. In contrast, LDR brachytherapy places a low activity radiation source into the tumor for a longer, e.g., indefinite, period of time.

Both forms of brachytherapy have advantages. For instance, HDR brachytherapy provides higher radiation levels delivered over a shorter dose delivery period. LDR brachytherapy, on the other hand, utilizes lower activity radiation sources. The energy field of the LDR radiation source results in a measured and localized dose of radiation delivered to the target tissue, e.g., the tumor, gland, or other surrounding tissue. However, the energy field thereafter decays to avoid excessive exposure of nearby healthy tissue.

Due in part to the lower activity of LDR radiation sources, LDR brachytherapy may provide various advantages. For example, for healthcare workers, exposure precautions for LDR brachytherapy may be less stringent than those for HDR brachytherapy. Moreover, for patients, the relatively longer implantation period associated with LDR brachytherapy may result in fewer visits to a healthcare facility over the course of radiation treatment.

Common radiation sources used in LDR brachytherapy include radioactive isotopes such as Palladium (Pd)-103, Iodine (I)-125, Gold (Au)-198, and Iridium (Ir)-192. While the size and shape of the isotopes may vary, they are, in common applications (e.g., prostate brachytherapy), provided in cylindrically shaped capsules that are approximately the size of a grain of rice, e.g., about 0.8 millimeters (mm) in diameter and about 4.5 mm in length, and are often referred to as “seeds.”

LDR seeds are often delivered through needles using a guide template. The guide template may include a matrix of holes that guide the longitudinal advancement of the needles to insure their proper position relative to the target tissue. Once the needles are properly located in the target tissue, the seeds may be deposited along the longitudinal axis of each needle, after which the needles may be withdrawn.

While effective, current brachytherapy implementations have potential drawbacks. For example, the LDR seeds are typically left indwelling and free floating within the target tissue and are, therefore, susceptible to migration. Moreover, once implanted, LDR seeds are generally not considered to be removable or repositionable. LDR brachytherapy may also require careful dose distribution calculations and seed mapping prior to, and often during, seed implantation. Such calculation and mapping allows effective radiation delivery to the target tissue volume, while minimizing radiation to surrounding healthy tissue (the urethra and rectum, for example, in prostate brachytherapy). Yet, while such dose calculation and seed mapping techniques are effective, problems—such as potentially significant variability in accuracy of seed placement among different clinicians—may exist.

Yet another issue with conventional LDR brachytherapy techniques is that many of these techniques often require the radioactive seeds to be manipulated individually at the time of implantation, an often time-consuming process. Moreover, conventional LDR delivery needles are generally limited to delivering the seeds linearly (along a relatively straight line). Thus, to achieve the desired therapy profile, numerous implants (e.g., about 50-100 seeds are common with prostate brachytherapy), in conjunction with potentially complex dose distribution and mapping techniques and equipment, are often required.

SUMMARY

The present invention is broadly directed to apparatus and methods for delivering brachytherapy to a localized target tissue region. While the invention is useful in treating most any area of the body, it offers particular advantages in the treatment of breast tissue, e.g., breast tumors or lumpectomy cavities. For example, the invention may be used to place and remove a localized radiation source for both neoadjuvant and post-excisional treatment.

In one embodiment, a flexible implantable brachytherapy treatment device is provided. The device may include one or more of: a therapy delivery portion including a non-dissolving casing; and one or more radiation sources fixed relative to the casing. In other embodiments, an elongate removal portion extending from the therapy delivery portion may be provided.

In another embodiment, a brachytherapy treatment device operable for both implantation into, and subsequent removal from, a target tissue region of a body is provided. The device may include a therapy delivery portion having one or more radioactive sources fixed relative to a casing, where the casing is operable to be positioned in direct contact with the target tissue region. The device may also include at least one non-dissolving flexible tail portion extending from the therapy delivery portion.

In yet another embodiment, a brachytherapy treatment device for implanting a plurality of radioactive sources into a target tissue region of a body, and for removing multiple radioactive sources at the completion of brachytherapy, is provided. The device may include a therapy delivery portion having a heat-shrinkable casing operable to securely retain the multiple radioactive sources. The device may further include a non-dissolving, first flexible tail portion extending from a first end of the therapy delivery portion, and a non-dissolving, second flexible tail portion extending from a second end of the therapy delivery portion.

In still yet another embodiment, a device for delivering brachytherapy to a target tissue region of a body is provided wherein the device may include an elongate, non-dissolving flexible casing adapted to securely hold therein a plurality of radioactive sources.

In yet another embodiment, a device for delivering brachytherapy to a lesion of the breast is provided, wherein the device includes a non-dissolving flexible casing adapted to securely hold therein a radioactive source.

In still another embodiment, a brachytherapy delivery apparatus is provided. The apparatus may include means for simultaneously implanting, in a parallel array, a plurality of catheters into a target tissue region, wherein each catheter of the plurality of catheters is operable to receive one or more radioactive sources.

In still another embodiment, a garment for attenuating radiation from an implantable brachytherapy device is provided. The garment includes a fabric portion operable to cover an area surrounding the brachytherapy device, and a radiation attenuating material associated with the fabric portion.

In still yet another embodiment of the invention, a kit for delivering brachytherapy to a target tissue region of a body is provided. The kit may include a removably implantable elongate brachytherapy device having: a therapy delivery portion; one or more radioactive sources secured to the therapy delivery portion; and at least one non-dissolving flexible tail portion extending from the therapy delivery portion. A catheter for delivering the brachytherapy device to the target tissue region may also be provided.

Another embodiment of the invention provides a catheter for implanting at least one radioactive source into a target tissue region of a body. The catheter may have a radiotransparent portion and a radioabsorptive portion, wherein the radioabsorptive portion extends substantially along a longitudinal length of a dose delivery portion of the catheter.

In still another embodiment, a catheter assembly for delivering one or more radioactive sources to a target tissue region of a body is provided. The catheter assembly may include a first catheter member and a second catheter member positionable within the first catheter member. The second catheter member may be operable to extend outwardly from an opening at or near a distal end of the first catheter member such that an axis of the second catheter member intersects an axis of the first catheter member.

In another embodiment, a catheter assembly for delivering a high dose radiation (HDR) source to a target tissue region of a body is provided. The catheter assembly may include a catheter shaft comprising a distal end and a proximal end, and an inflatable balloon coupled to the catheter shaft between the distal end and the proximal end. A dose delivery lumen may be provided and extend along the catheter shaft between the proximal end and the distal end. A dose delivery portion of the catheter shaft surrounded by the inflatable balloon may include a radioabsorptive portion.

In still yet another embodiment, a system for implanting a plurality of brachytherapy devices into a target tissue region of a body is provided. The system may include a catheter guiding template, a cartridge receiver associated with the catheter guiding template, and a pre-assembled cartridge having a plurality of delivery catheters arranged in a fixed relationship. The cartridge receiver is operable to receive the pre-assembled cartridge.

Yet another embodiment addresses a method of providing brachytherapy to a target tissue region of a body. The method may include providing an elongate brachytherapy device having: a therapy delivery portion with one or more radioactive sources secured thereto; and a non-dissolving flexible tail portion extending from the therapy delivery portion. The therapy delivery portion may be located at a static position within the target tissue region, wherein the flexible tail portion protrudes outside the body. Brachytherapy may be delivered with the one or more radioactive sources.

In still another embodiment, a method of providing brachytherapy to a target tissue region of a body is provided. The method may include simultaneously advancing multiple catheters into a target tissue region, and delivering one or more radiation sources through at least one catheter of the multiple catheters.

In still yet another embodiment, a method of providing brachytherapy to a target tissue region of a body is provided. The method may include simultaneously advancing multiple catheters into a target tissue region, and delivering one or more radiation sources through at least one catheter of the multiple catheters.

In yet another embodiment, a method for delivering brachytherapy to a lesion of the breast is provided. The method may include implanting a radioactive source at or near the lesion, delivering brachytherapy, and removing the lesion. The radioactive source may be removed prior to or during removal of the lesion.

The above summary of the invention is not intended to describe each embodiment or every implementation of the present invention. Rather, a more complete understanding of the invention will become apparent and appreciated by reference to the following detailed description and claims in view of the accompanying drawing.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Generally speaking, the present invention is directed to brachytherapy apparatus and methods. More particularly, the present invention provides a system for delivering one or more therapeutic elements (e.g., radiation sources) relative to a target tissue region. Once delivered, the radiation sources may be either immediately withdrawn (e.g., in HDR applications), or left in place, e.g., implanted, for a defined period (e.g., in LDR applications). In either instance, the radiation sources may deliver therapy to the target tissue region in accordance with a predefined therapy profile.

In some embodiments, LDR radiation sources may be implanted and secured to the body or target tissue in such a way as to prevent or substantially limit movement of the sources relative to the target tissue. Unlike conventional LDR brachytherapy, apparatus and methods of the present invention provide not only indwelling therapy using pre-arranged packages of radioactive sources, e.g., seeds, but also allow easy removal of the radiation sources at the completion of brachytherapy.

As used herein, “radiation source” may include most any therapeutic element operable to deliver a dose of radiation. For example, the radiation source may be a radioactive seed or, alternatively, a LDR or HDR wire element (e.g., Iridium wire).

The term “implantable,” as used herein, indicates the capability of a device to be inserted into the body and then maintained in a fixed or static position, relative to the immediately surrounding tissue, for an extended period of time, e.g., an hour or more and, more preferably, several hours or more.

Furthermore, “target tissue,” “target tissue region,” and “target tissue volume,” as used herein, may include most any portion of a human (or other mammalian) body that has been identified to benefit from radiation therapy. For example, the target tissue region may be a tumor or lesion itself, tissue proximate or surrounding the tumor, or a cavity created by tumor excision (such as the surrounding tissue associated with a lumpectomy cavity of the breast).

It should be noted that, while described herein primarily with respect to LDR brachytherapy, the apparatus and methods of the present invention may also have application to HDR brachytherapy (e.g., HDR catheters) as further described below. Moreover, while described herein with respect to brachytherapy, the present invention may have application to other therapy regimens that benefit from the removable implantation of therapy-delivering elements.

For the sake of brevity, the invention is described herein as it relates to the treatment of breast cancer. However, this particular application is not limiting. That is, those of skill in the art will readily appreciate that the systems, apparatus, and methods described herein may find application to most any cancer that may receive benefit from brachytherapy.

With this introduction, attention is now directed to the figures of the drawing.FIG. 1illustrates an exemplary kit or apparatus100for providing brachytherapy to a target tissue region of a body. The apparatus100may include an elongate and flexible, removably implantable brachytherapy treatment device102(also referred to hereinafter as “brachytherapy device102”) having a therapy delivery portion104, and an elongate and flexible tail portion106. The tail portion106may, as further described below, provide the ability to remove the device102at therapy completion. Other components described below, e.g., locking members, may also be included with the apparatus100.

The term “flexible” is used herein to describe a component that is highly pliant, e.g., a component that may be substantially and easily bent, flexed, and/or twisted without experiencing breakage or permanent deformation.

The therapy delivery portion104may form a carrier pod of therapeutic elements, e.g., radiation sources such as radioactive seeds108, secured relative to one another and to the therapy delivery portion104. One or more spacers110may optionally be located between each seed108to obtain the desired seed separation.

The seeds108may be produced from most any acceptable radioactive source now known (e.g., radioactive Palladium or Iodine) or later developed. Typically, numerous seeds108are provided and precisely placed along the length of the therapy delivery portion104in order to correspond to the desired therapy delivery regimen. While the radioactive sources are described herein as seeds108, they may take other forms such as a continuous filament (or numerous discontinuous segments) of radioactive wire (e.g., Iridium wire).

In some embodiments, the brachytherapy device102may include a flexible casing or casing member, illustrated in the figures as tube or tube member112, in which the seeds108and optional spacers110are securely retained. In some embodiments, the casing is made from a non-dissolving and flexible, heat-shrinkable tubing material. “Heat-shrinkable tubing,” as used herein, refers to tubing, such as various plastic tubing, in which subsequent thermal exposure causes the tubing to shrink, thereby allowing it to securely retain the seeds108in place. Exemplary heat-shrinkable materials include polyester, fluorinated polymers, and polyolefins.

While most any number of tubing sizes are contemplated, in one embodiment, the tube112may have an initial inside diameter of about I mm and a wall thickness of about 0.05 mm. Once heated, the tube112may shrink (if unconstrained) to an outer diameter ranging from about 0.3 mm to about 0.6 mm.

While the casing is described herein generally as tube-shaped, the casing may, in other embodiments, be most any shape that is capable of effectively securing the individual seeds108relative to the casing and to one another.

Once the seeds108and optional spacers110are located within the tube112, the tube may be shrunk by exposure to heat, thus contracting the tube112around the seeds108. The tail portion106may be formed by an integral portion, e.g., extension, of the casing (tube112) that extends beyond the seeds108. To reduce the diameter of the tail portion106, it may also be thermally treated (shrunk). Other embodiments (described below) may utilize a two-part brachytherapy device, e.g., a separate filament tail portion attached to the therapy delivery portion.

Regardless of the specific configuration, the brachytherapy devices102described herein provide not only proper spacing of the seeds108, but also facilitate subsequent seed identification and removal. Moreover, because the seeds are contained within the pod defined by the therapy delivery portion104, seeds may not require individual handling, thus simplifying inventory and handling prior to, and at the time of, implantation.

The components of the device102, including the casing (tube112) and tail portion106, are preferably constructed of non-dissolving materials. The term “non-dissolving” is used herein to indicate most any material that does not substantially deteriorate or otherwise break down during the implantation period.

The brachytherapy apparatus100may also include a catheter, e.g., needle114. While illustrated as needle114, any other type of catheter, such as the cannulae described further below, may also be used without departing from the scope of the invention. The needle114defines a lumen115of sufficient size to allow the therapy device102to pass through as indicated inFIG. 1. The needle114, in some embodiments, may further include a hub116at a proximal end to assist with manipulation of the needle and insertion of the therapy device102. A distal end of the needle114may form a sharpened tip117operable to pierce the body as further described below. The needle114may be made from most any suitable biocompatible material. For example, it may be made from metal, e.g., stainless steel, titanium, or nickel titanium alloy. It may also include a removable outer sheath (not shown) made of plastic, e.g., fluorinated polymers.

FIGS. 2A-2Eillustrate an exemplary method of using the brachytherapy apparatus100ofFIG. 1. Once a target tissue region202(a tumor or tumor cavity) within body200is accurately located, the needle114may be inserted into the body200, as shown by arrow203inFIG. 2A, to a predetermined depth. The relative location(s) of the needle114and/or the target tissue region202may be determined by most any method, e.g., via ultrasound, CT scan, stereotactic X-ray, etc. The needle114may further be aligned with the use of a needle guiding template as further described below, or by other techniques.

Next, the brachytherapy device102may be inserted into the lumen115of the needle114, as shown by arrow205inFIG. 2B, until the therapy delivery portion104is located at the desired depth relative to the target tissue region202as shown inFIG. 2C. To assist in determining the approximate insertion depth of the therapy device102, the tail portion106may include measurement demarcations118. Other location verification techniques, e.g., X-ray, ultrasound, etc., may also be used.

Once the therapy device102is located at the desired depth, the needle114may be withdrawn from the body in the direction207as shown inFIG. 2D, leaving the therapy delivery portion104of the device102at the desired position within the body200. The tail portion106is preferably of sufficient length such that it extends outside of the body200as shown inFIG. 2E. That is, the tail portion106may extend externally through a puncture made by the needle114.

In order to prevent migration of the therapy delivery portion104, a locking member120may be crimped or otherwise attached to the tail portion106of the therapy delivery device102immediately adjacent the associated puncture in the body200. The locking member120may assist in maintaining the location of the therapy delivery portion104relative to the target tissue region202. While most any locking member may be used, one embodiment utilizes a malleable, hat- or U-shaped lock that can be easily and securely crimped to the tail portion with, for example, a surgical clip applier or similar tool. An enlarged view of an exemplary locking member is illustrated inFIG. 27.

For illustration purposes, only a single therapy delivery device102is shown inFIGS. 2A-2E. However, in practice, multiple devices would be utilized to provide adequate dosage to the target tissue region202. The actual number of devices102may vary depending on various parameters such as lesion size, radiation source activity levels, and proximity to other organs/vulnerable tissue (e.g., skin, chest wall). However, quantities ranging from about 5 to about 25 devices are contemplated.

FIG. 2Fillustrates a variation of the therapy device102ofFIGS. 2A-2Ethat may offer additional benefits, especially to the treatment of breast cancers. In this embodiment, a therapy device152similar in most respects to the device102is provided. However, the device152may include both a first tail portion extending from a first end of a therapy delivery portion154and a second tail portion extending from a second end, i.e., it may include a tail portion156at each end of the therapy delivery portion154. During implantation, the needle114may pass completely through the body, e.g., breast200, such that one tail portion156extends out the opposite side of the breast200. In this way, locking members120may be secured at two locations relative to the target tissue region202, thus preventing or substantially limiting movement of the therapy delivery portion154relative to the target tissue region202.

Unlike conventional brachytherapy catheters, which may be 2 mm or more in diameter, the devices of the present invention, e.g., devices102, may be about 1 mm or less in diameter at the therapy delivery portion104and even smaller at the tail portion106. This construction permits the devices102to be relatively small and flexible, and thus less obtrusive to the patient. In fact, the size and flexibility of the tail portions106may be similar to that of a conventional suture. As a result, securing the tail portions106may be accomplished in any number of ways including, for example, folding the tail portions against the contour of the surrounding body and fixing them such as by tying the ends and/or securing the ends with adhesive, the latter represented by bandage2600inFIGS. 2E and 26.

FIG. 3Ais an enlarged view of the therapy device102ofFIG. 1. As clearly illustrated in this view, the therapy device102may include the therapy delivery portion104and the tail portion106. As described above, the therapy delivery portion104may include one, or preferably more, radioactive seeds108separated by spacers110and encased within the casing, e.g., heat-shrinkable tube112. The tail portion106may be formed by the portion of the tube112that does not surround the seeds108. In some embodiments, the conformal properties of the tube112may be sufficient to ensure proper seed spacing, thus negating the need for spacers110.FIG. 3Billustrates a section view through a seed108and the tube112taken along line3B-3B ofFIG. 3A.

FIGS. 4A-4Billustrate a therapy device402in accordance with another embodiment of the present invention. The device402is similar in many respects to the device102described above. For example, the device402may include a therapy delivery portion404and a tail portion406as illustrated inFIG. 4A. A casing, e.g., heat shrinkable tube412, may be used to encase the seeds108and optional spacers110as well as to form the tail portion406. However, unlike the embodiment ofFIGS. 3A-3B, the tube412may include a radioabsorptive portion414, e.g., a substance or liner, positioned along a portion of the circumference of the therapy delivery portion404(seeFIG. 4B). The radioabsorptive portion414may include a radiation attenuating material, and thus reduce radiation exposure to tissue blocked by the radioabsorptive portion414as opposed to tissue not blocked by the portion414. While not limited to any particular embodiment, the radioabsorptive portion may be formed by a substance (e.g., Tungsten, Nickel-Titanium alloy, stainless steel) applied to, or impregnated within, a portion of the tube412. Alternatively, the radioabsorptive portion(s) may be formed by a liner within, or secured to a portion of, the tube412.FIG. 4Billustrates a section view through a seed108and the tube412taken along line4B-4B ofFIG. 4A.

The term “radiotransparent” is used herein to indicate only that the identified portion of the apparatus or device is relatively more transparent to radiation than the portion identified as “radioabsorptive.”

FIGS. 5A-5Billustrate a therapy device502in accordance with yet another embodiment of the present invention. The device502is similar in many respects to the device102described above. For example, the device502may include a therapy delivery portion504and a tail portion506as shown inFIG. 5A. A casing, e.g., heat shrinkable tube512, may be used to encase the seeds108and optional spacers110as well as to form the tail portion506. However, unlike the previous embodiments, the therapy device502may incorporate an anchor member, e.g., a flat or round cross-section anchor wire514, which extends along at least a part of the therapy delivery portion504. The anchor wire514protrudes from one or both ends of the therapy delivery portion and may be bent to form one or more hooks or anchors516.

When the therapy delivery portion504exits the needle114(seeFIG. 1) during implantation, the anchors516may extend and engage surrounding tissue, thereby assisting in preventing migration of the therapy device502. While only a single anchor is shown at each end of the therapy delivery portion504, other embodiments may include multiple anchors at one or both ends to further resist movement, e.g., rotating or twisting.FIG. 5Billustrates a section view through a seed108and the tube512taken along line5B-5B ofFIG. 5A.

After the desired dose of radiation has been delivered, the therapy device102(or any of the other therapy devices described herein, e.g., devices402or502), may be removed in any number of ways. For example, the device102may be removed by first removing any dressing (e.g., bandage2600ofFIG. 2E) and locking member(s)120, and then simply applying a pulling force to one of the tail portions106that extends outside of the body200. Alternatively, the devices102may be removed prior to or during excisional surgery of the tumor202via known methods, e.g., via methods similar to excision utilizing localization wires.

Where the therapy device102includes internal retaining elements, e.g., anchors516of device502(FIG. 5A), a removal catheter550as shown inFIG. 5Cmay be used. The removal catheter550is similar in most respects to the delivery cannulae and needles described herein, e.g., needle114. The catheter550may be threaded over the tail portion106and advanced until it encompasses the therapy delivery portion104. For example, the removal catheter550may be advanced until its distal end engages the distal retaining element(s), e.g., distal anchor516ofFIG. 5A. Further advancement of the removal catheter550may bend the anchor sufficiently to permit the therapy delivery portion to slide into the removal catheter as shown in the broken line representation ofFIG. 5C. The device502and the removal catheter550may then be withdrawn as a unit from the body.

With any of the methods described herein, the time that the brachytherapy devices remain implanted may vary according to the desired therapy regimen. While not wishing to be bound to any fixed period, implantations from about one hour up to about eight weeks or more are contemplated for therapy. However, for breast brachytherapy, implantation periods ranging from about one day to several weeks are more likely. Moreover, because of the construction of the devices, e.g., devices102, they may be removed over a range of timeframes subsequent to implantation. This is in contrast to the permanent placement associated with conventional LDR brachytherapy and the short exposure time associated with conventional HDR brachytherapy. As a result, intermediate activity radiation sources may be utilized with the methods and apparatus of the present invention, as well as conventional low and, as further described below, high activity sources.

FIG. 6illustrates a brachytherapy kit or apparatus600in accordance with another embodiment of the invention. Unlike the apparatus100ofFIG. 1, the apparatus600may include, among other components, at least a removably implantable brachytherapy treatment device (brachytherapy device602), a pusher or pusher member620, a catheter, e.g., cannula or cannula member630, and a sharp obturator640.

The therapy device602, once again, may include a therapy delivery portion604and a removal or tail portion606. The therapy delivery portion604may include one or more seeds108and optional spacers110. The seeds108may be enclosed within a casing, e.g., heat-shrinkable tube or tube member612, similar in most respects to the tube112described above.

The tail portion606in this embodiment, however, is formed by an elongate filament or wire, e.g., a non-dissolving surgical suture614, coupled or otherwise attached to the therapy delivery portion604. While most any method of attaching the suture614to the therapy delivery portion604is possible, one embodiment forms a knot616in the suture. The knot616may be captured when the tube612is heat-shrunk to the therapy delivery portion604. In other embodiments, the suture614may be knotted around or otherwise attached directly to the therapy delivery portion604. Such suture attachment methods are exemplary only, however, as most any other method of attaching the suture614to the therapy delivery portion604is possible. The suture614, as with the tail portion106described above, is preferably made from a non-dissolving material, e.g., polypropylene, polyester, polyamide.

The pusher member620may include a lumen through which the therapy device602may pass as indicated inFIGS. 6 and 7. The pusher member may include a suture locking device622, e.g., a luer hub, at a proximal end to assist with loading and securing of the therapy device602. The locking device622may secure the suture614relative to the pusher620as further described below. While illustrated as a luer hub, the locking device622may include most any friction or clamping device known in the art. For example, the locking device may be an O-ring that may be selectively compressed to pinch the suture614.

The cannula member630may also include a lumen through which the pusher member620may pass as indicated inFIG. 6. The cannula member630may include a luer hub632at its proximal end that is operable to secure the cannula member relative to the either the sharp obturator640or the pusher member620when either is slid into the lumen of the cannula member as further described below.

The sharp obturator640may include a handle portion with a hub642at a proximal end, and a sharp point644operable to pierce body tissue at its distal end. The handle portion may permit comfortable manipulation of the obturator640. The external diameter of the obturator640may be sized so that it fits within the lumen of the cannula member630as indicated inFIG. 6.

The components of the apparatus600may be made from most any suitable biocompatible material. For example, the cannula member630, the pusher member620, and the sharp obturator640may be made from metal, e.g., stainless steel or Titanium, or plastic.

FIG. 7illustrates the apparatus600as it may be assembled prior to use. The sharp obturator640may be placed into the cannula630such that the sharp distal end644of the obturator protrudes from the distal end of the cannula630as illustrated. The therapy device602, which includes the therapy delivery portion604and the suture614as described above, may be positioned within the pusher member620such that the therapy delivery portion604extends from its distal end and the suture614extends from the hub622at its proximal end. The suture614may be pulled from the proximal end of the pusher member620until the therapy delivery portion604is at or near the distal end of the pusher member620as shown. The locking device622may then be engaged to hold the suture614, and thus the therapy delivery portion604, in place relative to the pusher member620.

FIGS. 8A-8Eillustrate an exemplary method of using the system600for delivery of brachytherapy to a portion of a body, e.g., breast200. Once the target tissue region202, e.g., tumor or tumor cavity, is identified, the combined cannula630and sharp obturator640(seeFIG. 7) may be advanced into the target tissue region202as illustrated by arrow802inFIG. 8A. When the distal end of the cannula630reaches the desired depth, the sharp obturator640may be removed (moved in the direction804) through the proximal end of the cannula as shown inFIG. 8B, while leaving the cannula630in place.

The combined pusher member620and therapy device602(seeFIG. 7) may then be inserted into the proximal end of the cannula630, in the direction806, as shown inFIG. 8C. The pusher620, and therapy device602, may be inserted until the therapy portion604is at its desired location, e.g., at or near the distal end of the cannula630. Location of the therapy portion604may be assisted by image guidance, e.g., stereotactic X-ray, ultrasound, CT, etc.

Once the therapy portion604is positioned, the cannula630may be retracted (moved in the direction808), exposing the therapy portion604to the target tissue region202as shown inFIG. 8D. The locking device622may then be unlocked such that the pusher member620and cannula630may be fully withdrawn (moved in the direction810) from the body200as shown inFIG. 8E. The therapy delivery portion604remains implanted at the target tissue region202while the suture614extends outside the body.

These steps may be repeated for placement of each brachytherapy device602, or multiple devices may be implanted as a group as further described below.

Although not illustrated, a locking member, such as the locking member120illustrated inFIGS. 2E and 27, may be used to secure the therapy device602, e.g., the tail portion(s)606, at one or both (seeFIG. 2F) ends. Alternatively, the therapy device602may include securing elements such as the anchors516shown inFIG. 5. Still further, the therapy device602may be secured simply by folding and adhering the tail portions606to the breast200(seeFIGS. 2E and 26).

After the desired dose of radiation has been delivered, the therapy delivery device102may be removed in any number of ways as already described herein, e.g., using a removal member, such as the tail portion606, or a removal cannula.

FIG. 9Ais an enlarged view of the therapy device602ofFIGS. 6-7. As clearly illustrated in this view, the therapy device602may include the therapy delivery portion604and the tail portion606. The therapy delivery portion604may include one, or preferably more, radioactive seeds108securely retained within the casing, e.g., heat-shrinkable tube612. The tail portion606may be formed by the suture614. The knot616of the suture614may be secured to the therapy delivery portion604by the heat shrinkable tube612. While shown as utilizing spacers110, they may not be required in some embodiments, e.g., the conformal properties of the casing, e.g., tube612, may be sufficient to ensure proper seed108spacing and containment.FIG. 9Billustrates a section view of the seed108and tube612taken along line9B-9B ofFIG. 9A.

FIGS. 10A-10Billustrate a therapy device1002in accordance with another embodiment of the present invention. The device1002is similar in many respects to the device602described above. For example, the device1002may include a therapy delivery portion1004and a tail portion1006. A casing, e.g., heat shrinkable tube1012, may be used to encase the seeds108and optional spacers110. Like the device602, the tail portion1006may be formed by a suture614having a knot616that may be heat shrinkable to the therapy delivery portion1004. However, unlike the device602ofFIGS. 9A-9B, the tube1012may include a radioabsorptive portion1014positioned along a part of the circumference of at least the therapy delivery portion1004(seeFIG. 10B). The radioabsorptive portion1014, which may be formed integrally or separately with the tube1012, may limit radiation exposure to tissue blocked by the radioabsorptive portion.FIG. 10Billustrates a section view of the seed108and tube1012taken along line10B-10B ofFIG. 10A.

FIGS. 11A-11Billustrate a therapy device1102in accordance with yet another embodiment of the present invention. The device1102is similar in many respects to the device602described above. For example, the device1102may include a therapy delivery portion1104and a tail portion1106. A casing, e.g., heat shrinkable tube1112, may be used to encase and constrain the seeds108and optional spacers110. Like the embodiment illustrated inFIGS. 5A and 5B, the therapy device1102may incorporate an anchor member, e.g., anchor wire1114, which extends along at least a part of the therapy delivery portion1104and protrudes from one or both ends. The anchor wire1114may be bent at one or both ends to form anchors1116. When the therapy delivery portion1104exits the cannula630(seeFIG. 8D), the anchors1116may extend and capture surrounding tissue, thereby assisting in preventing migration of the therapy device1102.FIG. 11Billustrates a section view of the seed108and tube1112taken along line11B-11B ofFIG. 11A.

It is to be understood that any of the various components of the invention described herein may be used interchangeably with any of the described methods and systems. For example, any one of the devices102,402,502,602,1002, and1102could be used with the methods described inFIGS. 2A-2E,2F, and8A-8E without departing from the scope of the invention.

The embodiments described above utilize a therapy delivery portion (e.g., portion104ofFIG. 1or portion604ofFIG. 6) formed primarily by the shrink fit tube (e.g., tube612ofFIG. 9A) and seeds108. However, other embodiments of the therapy delivery portion may include an additional support member. The support member may be any material that lends support to the therapy delivery portion, e.g., a strip of material such as stainless steel or superelastic nickel titanium alloy. In addition to partially supporting the seeds108, the material of the support member may divide the therapy delivery portion into a radiotransparent portion and a radioabsorptive portion. That is, it may partially surround at least a portion of the seeds108to provide some degree of attenuation or shielding of radiation to surrounding tissue. As a result, tissue on a side of the support member opposite the seeds108may receive a lower dose of radiation than tissue on the seed side. The support member may be enclosed within the casing, e.g., heat-shrinkable tube112or612.

For example,FIGS. 12A and 12Billustrate a therapy device1202having a tail portion1206and a therapy delivery portion1204with a plurality of seeds108and a straight support member1210(seeFIG. 12A). The support member1210may have a curved, e.g., arc-shaped, cross-section (seeFIG. 12B). Alternatively, a relatively flat cross-section (not shown) may be provided. Other embodiments may utilize most any other cross-sectional shape, e.g., v-shaped. The support member1210may also have a variety of leading edge shapes including the shovel-tip shape illustrated inFIG. 12A. Some or all of the support member1210may be encased within a casing, e.g., heat shrinkable tube1212, as already described above.

While the support member1210ofFIG. 12Ais generally straight, other support members in accordance with the present invention may be curved, e.g., may have some degree of curvature. For example,FIG. 13Aillustrates a therapy device1302having a therapy delivery portion1304with a curved support member1310that imparts an arc- or otherwise curved-shape to the delivery portion1304.

The support member1310may be formed to have curvature in its relaxed state or may simply be sufficiently flexible to permit curved implantation. As with the support member1210ofFIGS. 12A-12B, the support member1310may have most any cross-sectional shape, e.g., flat, curved (as shown inFIG. 13B), V-shaped, etc. Some or all of the support member1310may be encased within a casing, e.g., heat shrinkable tube1312, generally identical to the casings already described above.FIG. 13Billustrates a section view taken along line13B-13B ofFIG. 13A.

While not illustrated herein, support members in accordance with the present invention may include one or more slots, e.g., along a centerline, so that seeds may be placed at least partially within the slot. As a result, a therapy delivery portion that offers more rigidity than the unsupported therapy delivery portions described herein may be obtained while ensuring tissue on both sides of the support member receives radiation treatment.

FIGS. 14A-14Billustrate another exemplary embodiment of a therapy delivery portion1404. In this embodiment, the therapy delivery portion includes a catheter or casing, e.g., tube1412, having one or more lumens. A first or main lumen1408may receive the seeds (not shown), while a second lumen1414may contain an attenuating or shielding element1416extending over a longitudinal length of the tube1412. As a result, the tube1412may have a radiotransparent portion (that portion not blocked by the element1416), and a radioabsorptive portion (that portion shielded by the element1416). In one embodiment, the tube1412can be made by co-extruding plastic (e.g., fluoropolymer) with an attenuating material such as strands of fine metallic wire (e.g., stainless steel, gold). In another embodiment, the attenuating material may be a coextrusion of polymer loaded with an attenuating material such as Tungsten powder. The tube1412may or may not be heat-shrinkable. For versatility, the shielding element1416may be straight or preformed in a curve.FIG. 14Billustrates a section view taken along line14B-14B ofFIG. 14A.

FIG. 15is a partial view of an exemplary brachytherapy apparatus1500having a therapy device1502and catheter, e.g., cannula1501, wherein the device1502includes a curved therapy delivery portion1504, and a tail portion1506. Other components of the system, e.g., pusher member and sharp obturator, are not illustrated in this view. The curved therapy delivery portion1504may be formed by a curved support member such as support member1310ofFIG. 13A. The cannula1501preferably has a lumen diameter sufficiently large to accommodate the curved therapy delivery portion1504when the latter is constrained in a straightened configuration for delivery. Alternatively, the cannula1501may be sized to receive the therapy delivery portion1504when the latter is in its curved configuration. In still yet other embodiments, the therapy delivery portion1504may be generally straight but flexible and the cannula1501used to deliver the therapy delivery portion may be curved.

Non-linear (e.g., curved) catheters may also be used for delivery and placement of the brachytherapy devices described herein to regions and positions inaccessible to straight catheters. For example,FIGS. 16A-16Eillustrate an exemplary apparatus1650and method operable to implant a brachytherapy device, e.g., device102ofFIG. 1, along a non-linear axis.FIG. 16Aillustrates the apparatus1650including a first catheter member, e.g., needle1652, a second catheter member, e.g., flexible catheter1656, and a brachytherapy device102. The needle1652includes an off-axis opening1654at or near a distal end of the needle. The needle1652may be inserted into the body200, in the direction1651, until the distal end is positioned past the target tissue region202as shown inFIG. 16A. The flexible catheter1656may then be inserted through the needle1652(in the direction1653) until a distal end1667of the catheter1656protrudes from the opening1654of the needle1652at an angle1661as shown inFIG. 16B. That is, an axis of the catheter1656may intersect, or be otherwise nonparallel to, an axis of the needle1652.

The angle1661between the axes may vary, but angles ranging from greater than about 0 degrees to about 90 degrees, and more preferably about 5 degrees to about 35 degrees, are contemplated.

The device102may then be threaded through the catheter1656(in the direction1655), as shown inFIG. 16C, until the therapy delivery portion of the device102is located at or near the distal end1667of the catheter1656.

At this point, the catheter1656may be withdrawn slightly (in the direction1669) as shown inFIG. 16D, exposing the therapy delivery portion of the device102. The needle1652and catheter1656may then be withdrawn (in the direction1671) from the body200together as shown inFIG. 16E. The device102is then implanted on a non-linear axis with its tail portion106extending outside the body as generally described above with reference to other embodiments (see e.g.,FIGS. 2A-2E).

The ability to implant the device102along a non-linear axis may be beneficial in many applications. For example, where the target tissue region202is a breast lesion or a lumpectomy cavity in the breast, the non-linear device102may provide the capability to better focus radiation. Further, non-linear positioning may permit implantation around obstructions in the body. For example, in prostate brachytherapy, the region202could be a pubic arch around which the clinician desires to place radiation sources. While described above with respect to devices102, the non-linear placement ofFIGS. 16A-16Ecould also be used to implant individual radiation sources.

In yet other embodiments of non-linear placement apparatus and techniques, the needle1652ofFIGS. 16A-16Emay be replaced with a more spiral-shaped needle1675as shown inFIGS. 16F and 16G. While the actual needle size may vary depending on target tissue volume, needles having a helix diameter of about 3 centimeters (cm) are contemplated. The needle1675may be advanced into the body200in much the same way a corkscrew is inserted into a cork. That is, the needle1675may be rotated in a direction1678such that a sharp end1676penetrates the body200as indicated inFIG. 16F.FIG. 16Gillustrates the needle1675once it is fully inserted. A flexible catheter (not shown) and therapy device (also not shown) may then be passed through the needle1675in much the same way as the catheter1656and device102are described with reference toFIGS. 16A-16E. The needle1675may then removed (“unscrewed”), leaving the therapy device in a spiral configuration around the target tissue region202(not illustrated).

When non-linear, e.g., off-axis, curved, and spiral, therapy delivery portions are used, the total number of therapy devices required to treat a given target tissue region may potentially be reduced as a result of the delivery portions' conformance to the shape of the target tissue. For example, in the case of curved delivery portions, several devices may be placed to curve around the target tissue region, effectively focusing radiation on a central area. This may result in lower dose exposure outside of the target tissue area, and potentially improved dose coverage within the target tissue. In the case of a spiral therapy delivery portion, a single therapy device of sufficient length may deliver adequate treatment by spiraling (e.g., forming a helix) around or within the target tissue region.

FIGS. 17A-17Billustrate an apparatus1600similar in most respects to apparatus600ofFIG. 6. For instance, it may include a therapy device1602having a therapy delivery portion1604with seeds108, and tail portion formed by a suture1614. The suture1614may pass through a pusher member1620and the combined pusher member1620and delivery device1602may be placed within a cannula1630. Unlike the cannula630, however, the cannula1630may have a cutout1634, e.g., the cannula may have a C-shaped cross section, as shown more clearly inFIG. 17B, over at least a portion of its length. While shown as straight, the cannula1630may also be curved. The cutout configuration may protect certain surrounding tissues/organs, e.g., skin, chest wall, liver, heart, during implantation.FIG. 17Bis a cross-section taken along line17B-17B ofFIG. 17Awith the therapy delivery device1602also shown in broken lines.

During implantation of any of the devices described herein, the patient may optionally wear a protective garment, e.g., a chest covering brassiere or binder1900, such as that illustrated inFIG. 18. The brassiere/binder1900may be similar in many respects to those garments described, for example, in U.S. Pat. No. 3,968,803 to Hyman; U.S. Pat. No. 5,152,741 to Farnio; and U.S. Pat. No. 5,538,502 to Johnstone. That is, it may include a partial body covering that secures via fasteners, e.g., shoulder straps1904, to cover a portion of the chest (or other area surrounding the target tissue region). However, in addition to a fabric portion1906, the binder1900may include a lining made from a radiation attenuating material1902, e.g., lead, stainless steel, Tungsten. Such a garment may offer an added degree of shielding and permit greater patient mobility, while the radioactive sources, e.g., seeds108, are indwelling, in an out-patient setting. The garment1900may be provided separately, or as part of a brachytherapy kit, e.g., kit100.

Although discussed above primarily with respect to LDR brachytherapy, apparatus and/or methods of the present invention may also find use in HDR applications. For example, the tube1412ofFIGS. 14A-14Bmay be used as a shielded delivery catheter for HDR treatment, e.g., the tube1412may be located in the body and a conventional HDR source (e.g., afterload HDR cable) of smaller diameter may be passed through the main lumen1408. The attenuating element1416in the wall of the catheter (along a circumferential portion extending from about 10 o'clock to about 2 o'clock, for example) may attenuate the radiation exposure of regions vulnerable to radiation while the non-shielded section of the tube1412(along a circumferential portion extending from about 2 o'clock to about 10 o'clock) would allow exposure to the target tissue.

Further, for example, HDR radiation sources may be passed through a catheter, e.g., the cannula1630ofFIGS. 17A and 17B, whereby the HDR radiation sources may be partially shielded from surrounding tissue by the geometry of the cannula1630, e.g., the cutout1634.

FIGS. 19A-19Cillustrate incorporation of a HDR shielded catheter in accordance with the present invention on a balloon-type brachytherapy treatment device1800. The device1800may be similar to the device disclosed in U.S. Pat. No. 5,913,813 to Williams et al. That is, it may include a brachytherapy catheter assembly1802having a catheter shaft1814with a proximal end and a distal end. An inflatable balloon1806may be coupled to the catheter shaft1814between the proximal end and the distal end. An inflation lumen1830may extend along the catheter shaft1814between the inflatable balloon1806and the proximal end to allow inflation of the balloon. A dose delivery lumen1804(seeFIG. 19B) may also be provided and extend along the catheter shaft1814from the proximal end towards and the distal end, e.g., extending between the inflatable balloon1806and the proximal end.

In use, the distal end of the catheter shaft1814may be placed into a cavity, e.g., a lumpectomy cavity1808of breast200, and the balloon1806inflated. A radiation source (not shown) may then be passed through the dose delivery lumen1804, where it delivers radiation along a dose delivery portion of the catheter shaft, e.g., along a portion surrounded by the inflatable balloon1806. By incorporating a radioabsorptive portion (e.g., arc-shaped member1811clearly illustrated inFIG. 19C) over the dose delivery portion of the catheter shaft1814, only a predetermined portion, e.g., a window1817, of the dose delivery portion may be relatively radiotransparent. As a result, the device1800may attenuate the radiation exposure of select areas, e.g., those close to the skin or chest wall, while delivering higher radiation levels to target tissue not blocked by the radioabsorptive portion1811. While the radioabsorptive portion is illustrated herein as a separate member1811extending along a portion of the catheter shaft1814, other embodiments may incorporate the radioabsorptive portion into the catheter shaft1814itself (see. e.g., the catheters described elsewhere herein such as the tube1412ofFIGS. 14A-14B).

In some embodiments, the device1800may further include a vent system having one or more vents1810positioned around at least a portion of an outer surface of the balloon1806. The vents1810may permit air and fluids within the cavity1808to escape as the balloon1806expands. One or more vent lumens1812(shown inFIG. 19B) associated with the catheter shaft1814may extend between the proximal end of the catheter shaft1814and the one or more vents1810. The vents1810may fluidly communicate with one or more vent lumens1812, thereby allowing the air and fluids to exit the body at the proximal end of the catheter shaft1814during and after balloon expansion.

In some embodiments, the external vents1810and vent lumens1812are formed by individual pieces of tubing1816attached to the balloon1806and catheter shaft1814. In the vicinity of the balloon1806, the tubing1816may be perforated to form the external vents1810. The portion of the tubing1816located proximate the catheter shaft1814may or may not include perforations. The tubing1816may be formed of most any biocompatible material that can be securely attached to, or formed with, the balloon1806and catheter shaft1814, e.g., silicone tubing.

FIGS. 20-22illustrate an exemplary system1700for implanting the LDR brachytherapy devices and their associated radiation sources described above to a target tissue region, e.g., the region surrounding a breast lumpectomy cavity. In the illustrated embodiment, the system includes a catheter or needle guiding template1702having a predetermined number and pattern (array) of openings1704as shown inFIG. 20. The template1702may form part of an adjustable catheter or needle guiding apparatus by coupling to a stereotactic table1720, which is diagrammatically illustrated in the figures by base portion1722, and translating portion1724(portions1722and1724shown exploded inFIG. 20). The stereotactic table1720is preferably coupled or attached to a patient locating or treatment surface1730, e.g., patient table.

The template1702may be coupled to, or otherwise associated with, a first compression member1726located adjacent an opening1732in the treatment surface1730. An opposing second compression member1728may be located on an opposite side of the opening1732. The compression members1726and1728may be oriented about 90 degrees from a set of optional compression plates1727(only one plate1727shown).

One or both compression members1726,1728may include a hole pattern similar to that of the template1702, or may otherwise at least permit the passage of the needles/cannulae (e.g., needles114ofFIG. 1) as illustrated inFIG. 21.

In use, a patient may lie on the treatment surface1730, e.g., with the patient's head located in the direction1731, such that the breast200passes through the opening1732of the treatment surface1730. The optional compression plates1727may then be used to immobilize the breast200.

Once the breast200is immobilized, the stereotactic table1720, with the template1702attached, may be positioned, and the translating portion1724moved, until the compression members1726and1728contact the breast200. The position of the stereotactic table1720, and thus the needle guiding template1702, may be aligned with the location of the target tissue region202via the use of various imaging techniques including, for example, X-ray, ultrasound and CT scan. In some embodiments, the template1702may be aligned relative to the target tissue region based upon input provided by an imaging device, e.g., a side viewing ultrasound apparatus1739, located underneath the breast200.

With the template1702aligned with the target tissue region202and positioned against the breast200, one or more needles114may be inserted into the openings1704. In the treatment of breast lesions, the needles114may be inserted completely through the breast200as illustrated inFIG. 21. Alternatively, and in the treatment of other cancers, the length of each needle114may be varied to ensure the correct depth penetration at each opening1704, or the insertion depth of each needle114may simply be varied.

Certain embodiments of the system1700may optionally include an adhesive bandage member1750associated with the first compression member1726, and/or an adhesive bandage member1752associated with the second compression member1728. Preferably, the bandage members1750and1752are located between the respective compression members and the breast200. The bandage members1750and1752may have adhesive on each side, e.g., a first side1754and a second side1756, and include openings (not shown) that correspond generally to the openings1704of the template1702. Alternatively, the bandage members1750and1752may be punctured by the needles114during needle insertion. When the compression members1726and1728are pressed against the breast200, the bandage members1750and1752may adhere to the breast200and provide a dressing for the punctures created by the needles114.

Once the needles114are inserted, the brachytherapy devices described herein, e.g., devices102or602, may be inserted, and the needles114removed, in accordance with various methods as described and illustrated herein. For example, the brachytherapy devices102(or devices602) may be inserted and the needles114(or the cannulae630) removed in accordance with the methods described herein and illustrated inFIGS. 2A-2Eand2F (or8A-8E).

With the needles114removed, the template1702and contact plates1726and1728may be withdrawn from the breast200, leaving the bandage members1750and1752adhered to the breast by their respective first adhesive sides1754. The tail portions106may then be anchored, e.g., by using locking members such as members120illustrated inFIGS. 2E and 27.

A liner (not shown) may then be removed from the respective second adhesive side1756of each bandage member1750and1752. Once the second adhesive side1756is exposed, the flexible tail portions106may be folded against the second adhesive side, where they adhere thereto. A second, single-sided adhesive member (not shown) may be placed over each bandage member1750and1752to secure the tail portions and cover any exposed adhesive on the second adhesive side1756. As a result, the flexible tail portions may be folded against the contours of the breast and secured.

In some embodiments, the openings1704of the template1702may be grouped according to a particular target tissue volume, e.g., lesion size, as shown inFIG. 22. For example, a small square, five-opening pattern1740may be utilized for small target tissue regions (e.g., those regions up to about 1 centimeter in diameter), while a larger nine-opening pattern1742may be utilized for larger target tissue regions (e.g., those regions up to about 2 cm in diameter). A still larger, thirteen-opening pattern may be utilized for even larger target tissue regions (e.g., those regions up to about 3 cm in diameter).

By aligning the center opening of the template1702with the center of the target tissue region, the template may indicate a standard number of seeds, e.g., a particular number of therapy devices102, based upon the predetermined target volume. This could simplify, or possibly eliminate, the need for complex dose mapping calculations commonly associated with conventional brachytherapy methods.

It is noted that the patterns1740,1742, and1744are exemplary only. In other embodiments, the patterns may include most any number of openings1704in most any shaped pattern, e.g., a circular array of 5 to 50 catheters. Moreover, the templates could accommodate more that one diameter catheter or needle (e.g., 10, 15, and 20 mm diameters). Moreover, while shown with three patterns, templates having most any number are possible without departing from the scope of the invention.

FIGS. 23 and 24illustrate another system for implanting brachytherapy devices of the present invention.FIG. 23illustrates a system2300similar in many respects to the system1700described above. For instance, the system2300may include a stereotactic table2320secured to treatment surface, e.g., patient table (not shown). The table2320may include a base portion2322and a translational portion2324. The system2300may also include a first or proximal compression member2326and a second or distal compression member2328. One or both compression members2326and2328may be movable relative to the other and/or the base portion2322, e.g., along a slide rail2329.

Unlike the system1700, however, the system2300may also include a catheter or needle cartridge receiver2340operable to receive a pre-assembled needle cartridge2342having multiple needles114positioned in a predetermined array. The needle cartridge2342is shown in an exploded view inFIG. 24. The cartridge2342may include a first holder2344and a second holder2346(second holder2346not shown inFIG. 24). The holders2344and2346may include holes2348to hold and guide the multiple needles114in the desired predetermined array during insertion. Where needles114include a hub116, the holes2348in the holder2346may be larger than the corresponding holes2348in the holder2344to permit the passage of the hub116(seeFIG. 23).

During operation of the system2300, the stereotactic table2320may be aligned as described above with respect to the system1700. Once aligned, the breast200may be immobilized with the compression members2326and2328. Based upon the particular volume of the target tissue region202, a specific cartridge2342may be selected and pre-assembled with a corresponding number of catheters, e.g., needles114. For instance, the cartridge inFIG. 24is a 5 catheter configuration. However, other cartridges may utilize more or less catheters (e.g., 9 catheter and 13 catheter cartridges). The cartridge2342, including the holders2344and2346and the catheters114, may then be loaded into the cartridge receiver2340. Portions of the holders2344and2346may be designed to contact one or more internal surfaces of the cartridge receiver2340so that the cartridge2342aligns with the cartridge receiver upon insertion.

Once the cartridge2342is loaded, each needle114may be independently and manually advanced through the proximal compression plate2326(which may include a hole pattern identical to the holder2344), the breast200, and the distal compression member2328. The central needle114may be advanced first and its position within the target tissue region202confirmed (or repositioned) before the remaining needles are advanced. Brachytherapy devices, e.g., devices102ofFIG. 1, may then be placed into the needles114as described inFIGS. 2A-2E. Alternatively, the devices102could be pre-installed in the cartridge2342.

With the devices102inserted completely, the distal tips of the tail portions, see e.g., tail portion106ofFIG. 1, may be temporarily secured relative to the distal compression member2328. At this point, the needles114may be retracted and removed from the breast200, and ultimately, withdrawn from the cartridge loader2340. The proximal compression member2326may then be withdrawn and the proximal tail portions secured to the breast using, for example, the locking devices120described above and illustrated inFIGS. 2E and 27. The distal compression member2328may then be withdrawn and the distal tail portions secured relative to the breast200in a similar manner.

FIGS. 25A-25Dillustrate yet another system and method for inserting the brachytherapy devices of the present invention into a target tissue region.FIG. 25Aillustrates a system2500similar in many respects to the systems1700and2300described above. For example, the system2500includes a stereotactic table (not shown) having a catheter or needle cartridge receiver2540coupled thereto. The stereotactic table is preferably coupled to the treatment table (also not shown). The system2500may also include a catheter or needle cartridge2542. The needle cartridge2542may include a series of needles2514, e.g., 5, 9, or 13 needle array, which are generally rigidly and orthogonally mounted to a first plunger member2550. In this embodiment, the needles2514may be hubless as the proximal ends of the needles2514are secured (e.g., press fit, staked, adhered, etc.) to the first plunger member2550.

The cartridge2542may also include a first or proximal compression member2526(which may form the needle guiding template) as well as a second plunger member2552and an optional backing plate2554. In other embodiments, the backing plate2554may be part of the cartridge receiver2540. As with the systems previously described herein, the system2500may also include a second or distal compression member2528to assist in immobilizing the breast200.

During operation, the stereotactic table may be aligned such that the center of the needle cartridge receiver2540is centered relative to the target tissue region202. The cartridge2542may then be loaded into the cartridge receiver2540, and the breast immobilized by the first and second compression members2526and2528. The brachytherapy devices, e.g., devices102ofFIG. 1, may have been previously loaded into the needles2514of the cartridge2542. The first plunger member2550may then be advanced toward the breast200. Because the needles2514are rigidly coupled to the first plunger member2550, the needles2514advance simultaneously into the target tissue region of the breast200in the pre-determined parallel array. The first plunger member2550may include a tab2560that rides along a slot or surface2561of the cartridge receiver2540so that the first plunger member2550may be manually or automatically advanced from outside the cartridge.

After the first plunger member2550has been fully advanced as shown inFIG. 25B, the second plunger member2552may be advanced toward the breast200. The second plunger member2552has the proximal tail portions106of the brachytherapy devices102releasably secured thereto. Thus, advancing the second plunger member2552may advance one or more of the brachytherapy devices102into place such that the distal tail portions106emerge from the distal ends of the needles2514as shown inFIG. 25C.

The distal tail portions106may temporarily be secured to the distal compression member2528to hold the brachytherapy devices102in place. Once the distal tail portions106are secured, the proximal tail portions106may be released from the second plunger member2552and the first and second plunger members2550and2552may be retracted as shown inFIG. 25D. The cartridge receiver2540may also be retracted so that the proximal tail portions106may be secured in accordance with methods already described herein (e.g., locking members120). The distal tail portions106may then be disconnected from the distal compression member2528and the latter withdrawn. The distal tail portions106may then be secured relative to the breast200.

Thus, the system2500provide an apparatus for simultaneously implanting, in a two dimensional array, multiple brachytherapy devices into the body. Moreover, the systems described herein allow simultaneously advancing a two-dimensional array of catheters into a target tissue region, and then delivering or implanting one or more radiation sources through at least one of the catheters of the array. Once the radiation sources are implanted, sequential or simultaneous removal of the catheters of the array of catheters from the target tissue region may be accomplished.

As already described above, some embodiments may permit the tail portions106to be secured to the breast using an adhesive pad or bandage2600as illustrated inFIG. 26. Here, the bandage may be used in conjunction with, or as an alternative to, the locking members120.

To assist the health-care provider in securing the distal and/or proximal tail portions106, the compression members2526,2528may be configured as generally illustrated inFIG. 27. That is, openings2570in the plate (e.g., plate2528) through which the tail portions106pass may include a recess2572that holds the locking member120against the skin. As a result, when the compression plate2528is withdrawn, the locking member120may already be threaded over the tail portion106. The health care provider may then quickly crimp the locking member120, e.g., along a deformable portion2576.

The brachytherapy devices described herein may be implanted into (and/or around) the tumor prior to surgical excision (neoadjuvantly), and then subsequently removed before or at the time of surgery. Preferably, such treatments may shrink or even destroy the tumor. In other embodiments, the present invention may be used to deliver brachytherapy after surgical removal of the tumor tissue to treat surrounding tissue post-operatively (post-lumpectomy in breast). In some instances, it is contemplated that brachytherapy apparatus and methods described and illustrated herein may supplement or reduce the need for conventional treatment options, e.g., tumor excision, full field external beam radiation therapy (EBRT), and chemotherapy. Alternatively, the methods described herein may be performed adjuvantly with these and other treatments, e.g., with chemo, EBRT.

The brachytherapy devices described herein may also be both indwelling and removable. In contrast, conventional LDR and HDR brachytherapy seeds are typically one or the other—LDR seeds are generally indwelling but not removable while HDR sources are generally removable but remain indwelling only momentarily. As a result, the present invention may allow brachytherapy treatment at radiation activity levels greater than those commonly associated with LDR treatment while also permitting removal of the radioactive source. Moreover, treatment in accordance with the present invention may avoid some of the disadvantages of HDR treatment, e.g., high activity, exposure of unintended tissue, potentially bulky and protruding catheters, and the need for numerous patient visits to receive treatment.

The brachytherapy devices described herein are also substantially flexible, in comparison to conventional HDR catheters, such that they may be placed in either a straight or curvilinear (e.g., curved or spiral) fashion. Such flexibility may permit implantation of radiation sources (e.g., seeds) in configurations and locations that otherwise may be considered inaccessible.

Apparatus and methods of the present invention could also potentially achieve desired dosage with relatively few catheters. For example, apparatus and methods of the present invention could potentially obtain desired dose delivery levels with fewer catheters per target than is typically utilized with conventional HDR methods. Yet, the devices described herein may still be implanted with the use of conventional imaging methods (e.g. stereotactic X-ray, ultrasound, CT).

Apparatus and methods of the present invention may also provide other benefits to the patient. For example, potentially less skin damage and discomfort may result from smaller and more flexible catheter insertions. Further, the small flexible tail portions described herein may be folded and taped against the skin, unlike rigid HDR catheters. Thus, the patient may have less discomfort over the course of treatment and potentially improved post-procedural cosmesis. Further, for example, apparatus and techniques in accordance with the present invention may potentially result in reduced side effects as compared to other treatments, e.g., EBRT and chemo, and may require fewer hospital visits over the course of the treatment regimen as compared to, for example, current HDR brachytherapy.

Still further, the brachytherapy delivery systems described herein may provide a standardized dose of radiation based upon lesion size. As a result, the need for extensive dose calculating and mapping systems could potentially be reduced or eliminated with certain cancers (e.g., breast).

The complete disclosure of the patents, patent documents, and publications cited in the Background, the Detailed Description of Exemplary Embodiments, and elsewhere herein are incorporated by reference in their entirety as if each were individually incorporated.

Exemplary embodiments of the present invention are described above. Those skilled in the art will recognize that many embodiments are possible within the scope of the invention. Other variations, modifications, and combinations of the various components and methods described herein can certainly be made and still fall within the scope of the invention. For example, any of the treatment devices described herein may be combined with any of the delivery systems and methods also described herein. Thus, the invention is limited only by the following claims, and equivalents thereto.