bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cryotherapy for Liver Tumors: Current Status, Perspectives, Clinical Results, and Review of Literature
Authors: Seifert J. K. , Junginger T. 
Published: October 2014

Cryotherapy has gained importance as a locally ablative treatment option for patients with non-resectable liver tumors, especially metastases from colorectal cancer. We have used this technique since 1996 for the treatment of 77 patients with malignant liver tumors. Patient data was prospectively recorded and follow-up was until September 2002 or death. Fifty-five patients had colorectal cancer liver metastases, 16 metastases from other primaries and 6 had hepatoma. Forty patients had cryotherapy only and 37 had an additional liver resection. Morbidity and mortality were 22% and 1.3%, respectively. In 68% of patients with colorectal liver metastases and an elevated serum carcinoembryonic antigen-level preoperatively, it returned to the normal range following cryosurgery. For all 77 patients, median survival was 28 months with a 3- and 5-year-survival rate of 39% and 26%, respectively, and median survival was 29 months with a 3- and 5-year-survival rate of 44% and 26%, respectively, for the 55 patients with colorectal liver metastases. Local recurrence at the cryosite was observed in 13 of 65 patients (20%) with initially complete treatment. For cryotherapy to further establish as a treatment for malignant liver tumors in a time where many new local ablative techniques are developing, different goals need to be achieved. The trauma of the procedure and local treatment failure need to be minimized and survival results need to be optimized. Published studies and new possible fields of research regarding these goals are discussed.
In Treating Localized Prostate Cancer the Efficacy of Cryoablation is Independent of DNA Ploidy Type
Authors: Bahn Duke K. , Silverman Paul , Lee Fred , Badalament Robert , Bahn Eric D , Rewcastle John C. 
Published: October 2014

While the prognostic value of DNA ploidy has been well established for radical prostatectomy, external beam radiation, brachytherapy and androgen deprivation therapy its role as a survival outcome predictor for prostate cancer patients treated with cryoablation has not yet been examined. Anecdotal evidence suggesting that cryoablation may be independent of DNA ploidy type led to the implementation of the current study. Retrospective analysis of data including flow digital cytometry was performed on 447 archival specimens taken from patients who had undergone cryosurgical ablation of primary prostate cancer. Five-year biochemical disease free survivals (bDFS) (defined as PSA thresholds of 0.5 and 1.0 ng/ml) were determined with Kaplan-Meier analysis. Patients were grouped according to DNA ploidy types then stratified by Gleason grade, risk group, pre-surgical PSA level, and disease stage. Mean and median age of the cohort was 65 and 64.6 years. Mean follow-up was 65.7 months. The DNA ploidy status of the population was found to be 59% diploid, 13% tetraploid, and 28% aneuploid. Using PSA < 1.0 ng/ml criterion, the bDFS rates for diploid, tetraploid, and aneuploid were 78%, 75%, and 79% respectively. The bDFS rates using a PSA < 0.5 ng/ml criterion were 67%, 59%, and 69% for diploid, tetraploid, and aneuploid groups. No significant outcome differences were found in stratified analysis. This investigation demonstrates that the efficacy of cryoablation is independent of DNA ploidy type.
Coregistration of Dynamic Contrast Enhanced MRI and Broadband Diffuse Optical Spectroscopy for Characterizing Breast Cancer
Authors: Hsiang David , Shah Natasha , Yu Natasha , Su Min-Ying , Cerussi Albert , Butler John , Baick Choong , Mehta Rita , Nalcioglu Orhan , Tromberg Bruce 
Published: October 2014

A handheld scanning probe based on broadband Diffuse Optical Spectroscopy (DOS) was used in combination with dynamic contrast enhanced MRI (DCE-MRI) to quantitatively characterize locally-advanced breast cancers in six patients. Measurements were performed sequentially using external fiducial markers for co-registration. Tumor patterns were categorized according to MRI morphological data, and 3D DCE-MRI slices were converted into a volumetric matrix with isotropic voxels to generate views that coincided with the DOS scanning plane. Tumor volume and depth at each DOS measurement site were determined, and a tissue optical index (TOI) that reflects both angiogenic and stromal characteristics was derived from broadband DOS data. In all six cases, optical scans showed significant TOI contrast corresponding to MRI morphological information. Sharp TOI peaks were recovered for well-circumscribed masses. A reduction in TOI was found inside a tumor with a necrotic center. A broadened peak was observed for a diffuse tumor pattern, and an inflammatory septal case provided two TOI peaks that correlated qualitatively with MRI enhancement. These results provide qualitative confirmation of the common signal origin and complementary information content that can be achieved by combining optical and MR imaging for breast cancer detection and clinical management.
Evaluation of Integral Dose in Cranio-spinal Axis (CSA) Irradiation with Conventional and Helical Delivery
Authors: Peñagarícano José A. , Shi Chengyu , Ratanatharathorn Vaneerat 
Published: October 2014

In cranio-spinal axis (CSA) irradiation, patients are usually treated in the prone position with junctions between cranial and spinal fields. Collimator angle and pedestal rotations are introduced to obtain coplanar alignment of the matched junction. Furthermore, daily moving junctions are commonly used to feather out the junctional dose as additional safe-guards to avoid radiation myelopathy. Helical tomotherapy integrates linear accelerator and CT technology capable of delivering CSA treatment without geometric matches or feathering of junctions. The patient is treated with helical beams in the supine position. Since CSA is used mainly in the pediatric population, the potential increase in integral dose to structures or the whole body from linac- or tomotherapy-based IMRT raises concerns of increased rates of secondary malignancies. In this study, we will present an integral dose comparison between conventional CSA (3D) and helical delivery to the CSA (TOMO) utilizing the Tomotherapy Hi-ART system for three pediatric patients. Integral dose was calculated for organ at risk (OAR), two targets (PTV-BRAIN and PTV-SPINE), entire planning CT data set and to the healthy tissue (entire CT-DATA SET minus the PTV). Overall integral dose was 8% higher in the TOMO plans for Patients #1 and #3, but 2% lower in Patient #2. DVH analysis shows that TOMO plans give lower doses to larger volumes and higher doses to smaller volumes of tissue in all three cases. The advantages of the TOMO plans are minimization of matched junctions and better sparing of most OARs. With increased computational and memory power in the tomotherapy planning station, the excess integral dose to the healthy tissue can be re-distributed within the patient and in turn the total integral dose can be same or lower than in conventional delivery. The impact of a small increase in overall integral dose and the associated risks of secondary malignancies are unknown. Long-term follow-up is needed to answer this question.
Development of a Combined microPET®-MR System
Authors: Lucas A. J. , Hawkes R. C. , Ansorge R. E. , Williams G. B. , Nutt R. E. , Clark J. C. , Fryer T. D. , Carpenter T. A. 
Published: October 2014

As evidenced by the success of PET-CT, there are many benefits from combining imaging modalities into a single scanner. The combination of PET and MR offers potential advantages over PET-CT, including improved soft tissue contrast, access to the multiplicity of contrast mechanisms available to MR, simultaneous imaging and fast MR sequences for motion correction. In addition, PET-MR is more suitable than PET-CT for cancer screening due to the elimination of the radiation dose from CT. A key issue associated with combining PET and MR is the fact that the performance of the photomultiplier tubes (PMTs) used in conventional PET detectors is degraded in the magnetic field required for MR. Two approaches have been adopted to circumvent that issue: retention of conventional, magnetic field-sensitive PMT-based PET detectors by modification of other features of the MR or PET system, or the use of new, magnetic field-insensitive devices in the PET detectors including avalanche photo-diodes (APDs) and silicon photomultipliers (SiPMs). Taking the former approach, we are assembling a modified microPET® Focus 120 within a gap in a novel, 1T superconducting magnet. The PMTs are located in a low magnetic field (~30mT) through a combination of magnet design and the use of fiber optic ‘bundles’. Two main features of the modified PET system have been tested, namely the effect of using long fiber optic bundles in the PET detector, and the impact of magnetic field upon the performance of the position sensitive PMTs. The design of a modified microPET®-MR system for small animal imaging is completed, and assembly and testing is underway.
Spatially Fractionated GRID Radiation Treatment of Advanced Neck Disease Associated with Head and Neck Cancer
Authors: Huhn Jeniffer L , Regine William F. , Valentino Joseph P. , Meigooni Ali S. , Kudrimoti Mahesh , Mohiuddin Mohammed 
Published: October 2014

Advanced nodal disease associated with head and neck cancer warrants aggressive, often multi-modality therapy to maximize local-regional control. The expansion of a novel treatment paradigm developed by our institution includes the addition of a single-fraction of high dose spatially-fractionated radiation (GRID) to a conventional course of treatment. Between 1995 and 2002 a series of 27 patients (median age 65) with bulky N2-3 disease were treated. Median nodal tumor size was 7 cm. Two groups of patients were evaluated. Group 1 (N=14) patients received a median neck dose 69 Gy (range 54–79 Gy) plus GRID treatment. Group 2 (N=13) patients received a median neck dose of 59 Gy (range 54–72 Gy) plus GRID treatment followed by planned neck dissection. Patients were evaluated for local-regional control, pathological response, survival, and morbidity. Median time to follow-up for Group 1 was 10 months (range 3–44 months). Neck control was 93%. Disease specific survival was 50%. Morbidity was limited to soft-tissue related damage and was mild. Median time to follow-up for Group 2 was 38 months (range 5–116 months). Pathologic complete response rate was 85%. Overall neck control rate was 92%. Disease specific survival was 85%. Surgical morbidity was limited to three wound healing complications. GRID treatment may be safely added to conventional treatment management of locally advanced neck disease related to cancer with acceptable morbidity. It may improve pathologic complete response rates in those patients who undergo planned neck dissection, possibly leading to improved survival. In patients with inoperable bulky disease, addition of GRID enhances local-regional control.
RT_Image: An Open-Source Tool for Investigating PET in Radiation Oncology
Authors: Graves Edward E. , Quon Andrew , Loo Billy W. 
Published: October 2014

Positron emission tomography (PET) has emerged as a valuable imaging modality for the diagnosis and staging of cancer. However, despite evidence that PET may be useful for defining target volumes for radiation therapy, no standardized methodology for accomplishing this task exists. To facilitate the investigation of the utility of PET imaging in radiotherapy treatment planning and accelerate its integration into clinical radiation oncology, we have developed software for exploratory analysis and segmentation of functional imaging datasets. The application, RT_Image, allows display of multiple imaging datasets and associated three-dimensional regions-of-interest (ROIs) at arbitrary view angles and fields of view. It also includes semi-automated image segmentation tools for defining metabolically active tumor volumes that may aid creation of target volumes for treatment planning. RT_Image is DICOM compliant, permitting the transfer of imaging data and DICOM-RT structure sets between the application and treatment planning software. RT_Image has been used by radiation oncologists, nuclear medicine physicians, and radiation physicists to analyze over 200 PET datasets. Novel segmentation techniques have been implemented within this programming framework for therapy planning and for evaluation of molecular imaging-derived parameters as prognostic indicators. RT_Image represents a freely-available software base on which further investigations of the utlity of PET and molecular imaging in radiation oncology may be built. The development of tools such as this is critical in order to realize the potential of molecular imagingguided radiation therapy.
Technical Description, Phantom Accuracy, and Clinical Feasibility for Single-Session Lung Radiosurgery Using Robotic Image-Guided Real-time Respiratory Tumor Tracking
Authors: Muacevic A. , Drexler C. , Wowra B. , Schweikard A. , Schlaefer A. , Hoffmann R. T. , Wilkowski R. , Winter H. , Reiser M. 
Published: October 2014

To describe the technological background, the accuracy, and clinical feasibility for single session lung radiosurgery using a real-time robotic system with respiratory tracking. The latest version of image-guided real-time respiratory tracking software (Synchrony®, Accuray Incorporated, Sunnyvale, CA) was applied and is described. Accuracy measurements were performed using a newly designed moving phantom model. We treated 15 patients with 19 lung tumors with robotic radiosurgery (CyberKnife®, Accuray) using the same treatment parameters for all patients. Ten patients had primary tumors and five had metastatic tumors. All patients underwent computed tomography-guided percutaneous placement of one fiducial directly into the tumor, and were all treated with single session radiosurgery to a dose of 24 Gy. Follow up CT scanning was performed every two months. All patients could be treated with the automated robotic technique. The respiratory tracking error was less than 1 mm and the overall shape of the dose profile was not affected by target motion and/or phase shift between fiducial and optical marker motion. Two patients required a chest tube insertion after fiducial implantation because of pneumothorax. One patient experienced nausea after treatment. No other short-term adverse reactions were found. One patient showed imaging signs of pneumonitis without a clinical correlation. Single-session radiosurgery for lung tumor tracking using the described technology is a stable, safe, and feasible concept for respiratory tracking of tumors during robotic lung radiosurgery in selected patients. Longer follow-up is needed for definitive clinical results.
Retrospective Evaluation of Pediatric Cranio-Spinal Axis Irradiation Plans with the Hi-ART Tomotherapy System
Authors: Peñagarícano José A. , Yan Yulong , Corry Peter , Moros Eduardo , Ratanatharathorn Vaneerat 
Published: October 2014

Helical tomotherapy (HT) can be used for the delivery of cranio-spinal axis irradiation (CSAI) without the need for beam matching of conventional linac-based external beam irradiation. The aim of this study is to retrospectively evaluate HT plans used for treatment in nine patients treated with CSAI. Helical tomotherapy cranio-spinal axis irradiation (HT-CSAI) plans were created for each patient. Average length along the cranio-spinal axis of the PTV was 65.6 cm with a range between 53 and 74 cm. Treatment planning optimization and plan evaluation parameters were obtained from the HT planning station for each of the nine patients. PTV coverage by the 95% isodose surface ranged between 98.0 to 100.0% for all nine patients. The clinically acceptable dose variation within the PTV or tolerance range was between 0.7 and 2.5% for all nine patients. Doses to the organs at risk were clinically acceptable. An increasing length along the longitudinal axis of the PTV did not consistently increase the beam-on time indicating that using a larger jaw width had a greater impact on treatment time. With a larger jaw width it is possible to substantially reduce the normalized beam-on treatment time without compromising plan quality and sparing of organs at risk. By using a larger jaw width or lower modulation factor or both, normalized beam-on times were decreased by up to 61% as compared to the other evaluated treatment plans. From the nine cases reported in this study the minimum beam-on time was achieved with a jaw width of 5.0 cm, pitch of 0.287 and a modulation factor of 2.0. Large and long cylindrical volumes can be effectively treated with helical tomotherapy with both clinically acceptable dose distribution and beam-on time.
Stereotactic Radiotherapy for Ocular Melanoma: Initial Experience Using Closed Eyes for Ocular Target Immobilization
Authors: Miralbell Raymond , Caro Monica , Weber Damien C. , Elizalde Javier , Perez-Ochoa Agata , Villà Salvador , IgnacioToscas José , Martinez Pedro , Linero Dolors , Nouet Philippe , Escudé Lluís 
Published: October 2014

To assess the reliability and target positioning reproducibility with eyes closed in uveal melanoma patients treated with a micromultileaf-based linear accelerator dedicated for stereotactic radiotherapy. Five consecutive patients treated with curative radiotherapy for uveal melanoma were monitored for positioning reproducibility with resimulation CT scans performed every two days while on treatment (23 resimulation CTs available). All patients underwent MRIs of the orbits before simulation to help to define the target and organs at risk ( e.g., lenses, optic nerves, ciliary bodies, and lacrimal glands) in the simulation CT (MRI-to-CT bone registration). Patients were simulated, resimulated, and treated with eyes closed. Patient #1 was treated with 5 daily fractions while patients #2 to #5, were treated with 10 daily fractions. We chose the lens of the tumor-bearing eye as the structure to be controlled, assuming that correct repositioning of the lens should be a valid surrogate for correctness of target repositioning. Displacements (mean and standard deviations, SD) of the lens in the three axes were measured for each patient. Systematic and standard errors were calculated. Planning target volume (PTV) margins were estimated according to McKenzie et al. [ Phys Med Biol 45, 3331-3342 (2000)]. For both AP-PA and left-right shifts calculated SD were always below 1 mm, except for patient #4, who was treated with a non-customized bolus that pushed the globe backwards in a random fashion. In ideal set-up conditions PTV margins around the target were estimated to be 3 mm. Asking patients to close their eyes is a simple and reliable immobilization procedure when treating ocular tumors with stereotactic radiotherapy. Margins of 3 mm around the target may be necessary to safely treat these tumors under ideal set-up conditions.
Facility Overview for a Proton Beam Treatment Center
Authors: Lesyna David 
Published: October 2014

Proton beam therapy is now widely recognized as the most precise form of radiation treatment available for certain types of diseases. As such, there is an ever-increasing demand for efficient hospital-based systems capable of providing proton therapy on a routine basis. A hospital-based proton-beam treatment center consists of many systems that must be integrated to form a single simple-to-operate and maintain medical device. The system must be capable of accelerating the proton beam to the needed energies safely and effectively, transporting the beam successfully to the appropriate treatment room, and shaping the proton beam to the desired target volume within the patient. This paper overviews the major systems needed to meet these objectives as part of a complete proton-beam treatment system. This paper focuses on the areas of beam acceleration, beam transport, and beam delivery methods, including an introduction to both passive and active beam delivery methods. Additionally, it introduces and provides examples of the required simplicity and types of automation needed to achieve a high-capacity proton-beam treatment system, with specific examples based on use at the system at Loma Linda University Medical Center.
The Use of Tissue Electrical Characteristics for Breast Cancer Detection: A Perspective Review
Authors: Ng E. Y. K. , Sree S. Vinitha , Ng K. H. , Kaw G. 
Published: October 2014

Breast cancer is the most frequently occurring malignancy in women. It is characterized by a high mortality rate. For the purpose of detecting this life threatening disease, research efforts are being made worldwide to exploit new technologies, to improve the detection accuracy of current devices and to develop new detection devices, comprehensive diagnostic procedures, and protocols. One such technology that is gaining popular attention over the recent years is the usage of electrical characteristics of the breast tissue to differentiate normal and cancerous tissues. Most of the devices using this technology are currently being used as adjunct diagnostic tools to improve the detection accuracy of established techniques like mammography and ultrasound. Also, early detection of breast cancer can help save many thousands of lives every year and can also reduce unnecessary healthcare expenditure caused by advanced stage treatment options. Hence, more research is also being done to adapt these devices into screening tools for early detection of breast cancer. The main objective of this review is to highlight the features of the currently available commercial devices that use this technology for breast cancer detection. The electrical behavior of normal and cancerous breast tissues is first presented. The various commercial devices that utilize electrical impedance or electropotentials for breast cancer detection are then described. Finally, conclusions and potential areas of research are highlighted.