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Nuclear Regulatory Commission (NRC) 

Advisory Committee on the Medical Use of Isotopes (ACMUI) 

Subcommittee on

Radioactive Seed Localization for Non-Palpable Breast Lesions 

Response to NRC Working Group Draft “Low Activity Radioactive Seeds Used for 

Localization of Non-palpable Lesions and Lymph Nodes Guidance” 

Final Report 

Subcommittee Members: 

Dr. Ronald Ennis (Chair) 

Mr. Frank Costello 

Dr. Darlene Metter 

Dr. Pat Zanzonico 

 

Introduction 

This subcommittee has previously presented on this topic in a report dated August 11, 2015. The 

recommendations in that report were presented to the ACMUI at its meeting on October 08, 2015. 

Since then, Dr. Philip Alderson has been appointed Chairman of the ACMUI. As a result, he has 

chosen not serve on this subcommittee for neutrality purposes. In addition, Dr. Darlene Metter was 

appointed to the ACMUI in March 2016 as the Diagnostic Radiologist representative. With the 

departure of Dr. Alderson from the subcommittee and 

Dr. Metter’s appointment and expertise, she was added to the subcommittee membership. 

Written Directive 

The most significant change from our subcommittee’s recommendations in the NRC/Agreement 

State Working Group (WG) Draft, “Low Activity Radioactive Seeds Used for Localization of NonPalpable Lesions and Lymph Nodes Guidance,” hereafter referred to as WG Draft Guidance, is the 

elimination of the requirement for a written directive (WD).The rationale for this recommendation 

is that a WD is required for therapeutic and certain diagnostic procedures. Since RSL is neither a 

therapeutic nor a diagnostic procedure, but rather a localization procedure, a WD is not required. 

Furthermore, elimination of a WD does not eliminate the possibility of a Medical Event (ME) and 

all of the standard ME criteria still apply. The subcommittee accepts this change on the basis of an 

implicit understanding that there will be documentation in the patient’s medical record of the 

Authorized User (AU)’s intention prior to the Radioactive Seed Localization (RSL) procedure and 

post-procedure documentation in the medical record documenting what was actually performed. It 

is the understanding of the subcommittee that this documentation will provide regulators with the 

required information to assess that an RSL procedure had been performed in accordance with the 

applicable regulations. 

Authorized User 
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Another significant change in the WG Draft Guidance is the creation of an alternative pathway to 

become an AU for RSL. In this pathway, radiologists whose training and experience did not qualify 

them for AU status under 35.290 or surgeons can become AUs for RSL with 80 hours of training 

and experience including a minimum of 40 hours of classroom and laboratory training in basic 

handling techniques applicable to the medical use of sealed sources. The subcommittee 

understands that a gap in training and experience exists for some radiologists who are active in the 

area of needle localizations and biopsies under image guidance (e.g. mammographers who routinely 

perform biopsies and place clips in the breast). Such physicians are the ones who most naturally 

would be called upon to place radioactive seeds for this diagnostic purpose. However, even if their 

training and experience was not enough to achieve 35.290 AU status, their radiology training (i.e. a 

residency in radiology) provided substantial background in all aspects of the medical use of 

radiation including safety, protection, biology and physics. Accordingly, the subcommittee 

supports an alternative (i.e. non-35.290) pathway for these radiologists to achieve AU status for 

RSL. However, the subcommittee believes strongly that surgeons or others without a significant 

background in radiation (from a residency or some other similarly intense education and practical 

experience) would be entirely unqualified to function as an AU for RSL with only 80 hours of 

training. 

Medical Event Reporting 

The WG Draft Guidance has added a new section for ME reporting. The WG Draft Guidance did 

not include the time component from the definition of ME that was recommended in the previous 

RSL Subcommittee Report (administration of radioactive byproduct material for more than 20% 

longer than planned). This component is replaced with the following criterion: an ME has occurred 

“...if the licensee fails to perform the explantation surgery,” with the caveat that such an outcome 

would not be an ME if “the physician makes the determination not to explant the seed for various 

patient conditions (e.g. doing so would jeopardize the patient’s well-being.)” The subcommittee 

accepts this change and support the exclusion from ME the situation in which the physician deems 

removal not to be in the best interest of the patient. Additionally, the subcommittee supports the 

position that an ME has not occurred in the event the patient failed to return for the surgical removal 

procedure, considering this to be an instance of “patient intervention”, provided the patient has been 

properly counseled about the importance of returning for the procedure and the risk of radiation 

exposure should the sources not be removed. Documentation of this counseling should be made in 

the patient’s medical record. 

Safety Precautions 

The subcommittee is disappointed the WG Draft Guidance does not include an explicit requirement 

to advise patients who have undergone RSL of the breast not to breast feed with the implanted 

breast until the seed has been explanted. The subcommittee is concerned about the exposure of a 

newborn child to even small doses of unnecessary radiation and the potential risk to that child later 

in life. It is well known to those trained in radiation safety and human health that the damaging 

effects of radiation are much more pronounced in children. However, the public and medical 

professionals who are not highly educated in issues of radiation safety and human health may be 

unaware of this distinction. Therefore, a mother may assume if it is safe for her to have this 
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radioactive seed in her breast, it is also safe for her baby to be exposed to the radiation via breast 

feeding. The subcommittee, therefore, feels this is an important omission and recommends inclusion 

of the following in the Draft Guidance: “Patient should be advised not to breast feed from a breast 

into which one or more radioactive seeds been implanted and not yet removed. Breast feeding is, of 

course, permissible once the seed(s) has(ve) been removed. In the event of seed rupture within the 

breast, the subcommittee recommends the patient be advised to never breast feed from either breast 

for this child.”(Note: The end time of the restriction on breast feeding in the setting of a ruptured 

seed has been changed from “10 half-lives”, which had been recommended in our previous 

recommendation, to “this child” to make this recommendation consistent with the recommendations 

for I-131.) 

Other recommendations 

The subcommittee agrees with the remainder of the WG Draft Guidance, including those portions 

related to previous recommendations of the subcommittee (see Subcommittee’s previous report 

dated August 11, 2015). 

Respectfully submitted, June 24, 2016 

Subcommittee on Radioactive Seed Localization for Non-Palpable Breast Lesions, 

Advisory Committee on the Medical Use of Isotopes (ACMUI), 

Nuclear Regulatory Commission (NRC) 

This report was unanimously approved by the Committee during its public teleconference 

meeting held on June 24, 2016.