ML12228A606

Permanent Implant Brachytherapy Medical Event Reporting Under 10 CFR Part 35

ML12228A606
Person / Time
Issue date:	07/30/2013
From:	Brian Mcdermott NRC/FSME/DMSSA
To:
Zelac R
Shared Package
ML13156A195	List: ML12228A606
References
EDATS-SECY-2012-0415, SECY-2012-0415, WITS 201200139 RIS-13-010
Download: ML12228A606 (8)

See also: RIS 2013-10

Text

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF FEDERAL AND STATE MATERIALS AND

ENVIRONMENTAL MANAGEMENT PROGRAMS

WASHINGTON, DC 20555

July 30, 2013

NRC REGULATORY ISSUE SUMMARY 2013-10

PERMANENT IMPLANT BRACHYTHERAPY MEDICAL EVENT

REPORTING UNDER 10 CFR PART 35

ADDRESSEES

All U.S. Nuclear Regulatory Commission (NRC) medical-use licensees, NRC master material

licensees (MMLs), Agreement State Radiation Control Program Directors, and State Liaison

Officers.

INTENT

The NRC is issuing this regulatory issue summary (RIS) to: (1) supply information to assist

licensees in complying with the current NRC requirements related to permanent implant

brachytherapy; and (2) announce that an Interim Enforcement Policy1(IEP), has been developed

and published and explain the enforcement discretion NRC will use to provide regulatory relief

to licensees until the implementation date of a revised final rule (10 CFR Part 35, Medical Use

of Byproduct Material) associated with the Medical Event (ME) reporting requirements.

No specific action or written response is required. The NRC is providing this RIS to Agreement

States for their information and for distribution to their medical licensees, as appropriate.

BACKGROUND

In SRM-SECY-12-00532, dated August 13, 2012, the Commission approved the staffs

recommendations for modifying the regulatory requirements that appear in 10 CFR 35.3045 for

permanent implant brachytherapy ME reporting and conforming changes to the current written

directive (WD) requirements in 10 CFR 35.40(b)(6), to convert from dose-based to

source-strength-based ME criteria for the treatment site. The Commission also directed the

staff to clarify ME reporting for permanent implant brachytherapy under the existing rule and

provide insights about compliance with the current NRC requirements. Finally, the Commission

directed the staff to develop an IEP that would allow the staff to exercise enforcement discretion

for both existing and future violations of current Part 35 that do not result in the misapplication of

byproduct material by those licensees that use total source strength and treatment (exposure)

time for determining the existence of a treatment site ME.

ML13156A195

_____________________

1

Docket ID NRC-2013-0114. Available on the Federal Rulemaking Web site at:

http://www.regulations.gov.

2

Available on the NRC public Web site in the Agencywide Documents Access Management

System at: http://www.nrc.gov/reading-rm/adams.html. Use search number ML12228A606.

RIS 2013-10

Page 2 of 7

SUMMARY OF ISSUE

Compliance With Current Regulations

In 10 CFR 35.2, Definitions, prescribed dose for manual brachytherapy is defined as either

the total source strength and exposure time or the total dose, as documented in the written

directive, and treatment site is defined as the anatomical description of the tissue intended to

receive a radiation dose, as described in a written directive. In 10 CFR 35.40, Written

Directives (WD), the information required for the WD when the treatment mode is manual

brachytherapy includes the patients or human research subjects name and the following:

Before implantation, the treatment site, the radionuclide, and the dose (i.e., the prescribed

dose); and after implantation but before completion of the procedure, the treatment site, the

radionuclide, the number of sources (implanted), and the total source strength and exposure

time (or the total dose).

The regulations reference many different terms all linked to the WD: total source strength; total

dose; treatment site; and dose. These terms may have variable meanings and uses for

licensees. For instance, in manual prostate brachytherapy, treatment site may mean the

prostate only for one licensee and may mean the prostate plus a volume of tissue surrounding

the prostate for another licensee. Therefore, licensees are reminded to be consistent in their

use of terms when documenting in the pre-implantation and post-implantation portions of the

WD all components of the implant that will ultimately be used when evaluating the adequacy of

the implant.

10 CFR 35.41, Procedures for administrations requiring a written directive, states that a medical

use licensee authorized for permanent implant brachytherapy must develop, implement and

maintain written procedures to provide high confidence that, among other things, each

administration is in accordance with the treatment plan, if applicable, and with the WD.

Therefore, licensees should have checks in place to ensure that each component of the WD is

met. The NRC notes that some licensees procedures were developed when the predecessor to

10 CFR 35.41, called Quality Management Program, was initiated (1990s) and licensees have

not updated these procedures even though their implant style and assessments may have

changed. For instance, prior to 1990, many licensees implanted sources for prostate treatments

without pre-planning or post-planning dosimetry. Today, many licensees perform extensive

imaging and dosimetry to prescribe and evaluate doses to not only intended tissue (e.g.,

prostate), but also to nearby tissue (e.g., rectum, bladder, or urethra). Therefore, licensees are

reminded that procedures should correctly document the program currently in place, and for

purposes of determining whether medical event reporting is required, provide definitive criteria

for evaluating the adequacy of the dose delivered to the intended treatment site, compared to

the prescribed dose, and the acceptability of the dose delivered to any other organ or tissue,

compared to the dose expected from the administration defined in the written directive.

10 CFR 35.3045, Report and notification of a medical event, provides the criteria for ME

reporting and uses terms like dose, prescribed dose, organ or tissue other than the treatment

site, and migrated seeds. These terms again may have variable meanings and uses for

licensees. In addition, differences in prescribing doses among licensees makes it difficult for

some licensees to assess if an ME has occurred.

RIS 2013-10

Page 3 of 7

For instance, in manual prostate brachytherapy, some licensees develop a treatment plan that

includes expected doses to organs or tissues near the prostate and perform post-treatment

planning after the implant with this same data. However, some licensees do not perform

treatment planning at all, but instead rely on a nomogram approach for performing implants and

review of post-implant images for assessing the adequacy of the placement of the sources.

Therefore, the first category of licensees may have data to assess whether an organ or tissue

other than the treatment site received a dose (in terms of gray (Gy) or rads) in excess of the

ME reporting criteria, but the second category of licensees would not readily have the data

available to make this assessment. NRC has noted that both categories of licensees frequently

do not document their post-treatment assessments in detail. In addition, the second category of

licensees should develop mechanisms for collecting definitive data to perform an assessment of

the adequacy of the implant. For instance, a conventional x-ray taken immediately after the

implant and reviewed may not be sufficient for determining where the sources are implanted.

Therefore, all licensees are reminded that their procedures, developed in accordance with 10 CFR 35.41, should be robust enough to allow the licensee to definitively evaluate the dose to

the defined treatment site and the doses to other organs or tissues in performing an assessment

of whether an ME may have occurred.

Total Dose Variance Determination

For the treatment site, the ME reporting criteria in 10 CFR 35.3045(a)(1) includes a threshold for

delivered total dose variance from prescribed dose, in sieverts (Sv) or in rem, and a threshold

for percent variance of delivered dose from prescribed dose. Both of these dose thresholds

(delivered total dose variance and percent dose variance) must be exceeded for a medical use

procedure to be deemed an ME based on treatment site dose variance.

As stated above, prescribed dose is defined as either the total source strength and exposure

time, or the total dose, as documented in the written directive. Section 35.3045 does not

explicitly state whether the comparison of delivered total dose to prescribed dose for the

treatment site, for determination of the percent dose variance, can be done with these doses

expressed as total source strength and exposure time, consistent with one of the options in the

definition of prescribed dose, or whether the prescribed dose (and the delivered total dose) must

be expressed as total dose, the other option in the definition of prescribed dose. However,

because 10 CFR 35.3045(a)(1) specifies that the threshold for delivered total dose variance

from prescribed dose is expressed in sieverts (Sv) or in rem in 10 CFR 35.3045(a)(1), section

35.3045 requires that this comparison of delivered dose to prescribed dose must be performed

in terms of total dose to determine whether a ME has occurred. Thus, Section 35.3045 does

not provide licensees with the option to use total source strength and exposure time in lieu of

total dose for the total dose variance determination.

Medical use licensees authorized for permanent implant brachytherapy are advised that for

completing the WD after implantation, the delivered dose (for the treatment site) may be

expressed as total source strength and exposure time as long as the prescribed dose was also

expressed in terms of total source strength and exposure time for the pre-implantation entries of

the WD. However, as noted above, the determination under section 35.3045(a)(1) that a

particular procedure is or is not an ME based on treatment site dose variance must be done with

both the delivered dose and the intended (prescribed) dose expressed in Sv or rem for

determination of total dose variance.

RIS 2013-10

Page 4 of 7

Therefore, in order for the licensee to be in compliance with the requirements in section

35.3045(a)(1), if specifying treatment site doses in the WD in terms of total source strength and

exposure time, the licensee should also provide sufficient information to allow for the calculation

of the total doses (prescribed and delivered) in Sv or rem. Of course, for the WD, medical use

licensees authorized for permanent implant brachytherapy can also continue to express both

the prescribed dose and the delivered dose as total doses, and make the determination under

section 35.3045 as to whether a treatment site ME has occurred based on the total dose values

(prescribed and delivered) in the WD. Note that an implant that is considered ME reportable

based on the percent dose variance for a comparison of delivered total dose to prescribed total

dose might not be considered ME reportable if the comparison of delivered dose to intended

dose was performed based on total source strength and exposure time.

As interim guidance to NRC inspectors when reviewing permanent implant brachytherapy

programs, in 2012 the NRC developed Appendix B, Reviewing Licensees Implementation of

Procedures for Permanent Implant Brachytherapy Administrations, and Appendix C, Questions

& Answers for Inspecting Manual Brachytherapy Prostate Implants, to its Inspection Procedure (IP) 87132, Brachytherapy Programs. Licensees may find these guidelines and examples,

along with the IEP described below, useful in reviewing their permanent implant programs and

procedures. These Appendices are enclosed, as well as being available on the NRC public web

site. Note that the IEP may supersede some of the information in IP 87132, including some of

the responses to the questions and answers in Appendix C, until IP 87132 is revised to reflect it.

However, note that, because the prescribed dose is large and is intended to be therapeutic, if

the percent variance of delivered total dose from prescribed dose for the treatment site exceeds

the threshold for reporting an ME, which is 20 percent, in every case the threshold for total dose

variance (delivered from prescribed) for the treatment site, at 0.5 Sv (50 rem), will also be

exceeded, so the two linked criteria for a treatment site ME will both have been met. This fact is

the basis for part of the enforcement discretion in the IEP described below.

Interim Enforcement Policy

Based on the information in the paragraph above, NRC recognized the need to provide

regulatory relief to licensees from the current requirement that a comparison of delivered dose

to prescribed dose for determination of total dose variance for the treatment site be done with

both doses expressed in Sv or rem. Specifically, provision of regulatory relief would be

justifiable in the case in which a licensees procedure identifies use of total source-strength and

exposure time for the entire process, including determining percent variation of delivered total

dose from prescribed dose as a criterion to identify a treatment site ME.

The NRC staff is currently revising the regulations in 10 CFR Part 35 for permanent implant

brachytherapy programs which may eliminate dose-based medical event reporting requirements

for treatment sites. In the interim, the NRC developed an IEP.

RIS 2013-10

Page 5 of 7

On July 9, 2013, the IEP was published in the Federal Register (78 FR 41125). The effective

date of the IEP is July 9, 2013. The NRC Enforcement Policy can be found at:

http://www.nrc.gov/about-nrc/regulatory/enforcement/enforce-pol.html. Via the Federal Register

Notice, the NRC provided notice of its revised Enforcement Policy. To review the IEP, please

refer to Enclosure 3.

The IEP applies to violations that result from an otherwise appropriate use of total source

strength and treatment time for determining the existence of a treatment site ME, and if use of

these values does not result in the misapplication of byproduct material by the licensee. Under

the IEP, enforcement discretion for existing and future violations of the ME reporting

requirement will be considered if the authorized treatment mode is permanent implant

brachytherapy and licensees uses total source strength and exposure time for determining the

percent variation between delivered total dose and intended (prescribed) dose (for the treatment

site), for determining under current 10 CFR 35.3045 whether a treatment site ME has occurred.

Enforcement discretion will only be considered if the licensee entered both the prescribed dose

and the delivered total dose into the WD in terms of total source strength and exposure time; the

licensee's documented procedures required under section 35.41 specify total source strength

and exposure time as the regulatory evaluation values for treatment site dose comparisons;

and the licensee timely reported the event based on that treatment site dose comparison, if

applicable.

The IEP also provides enforcement discretion for existing and future violations of the current

section 35.3045(a)(1)(i) ME reporting requirement when a treatment site total dose exceeds 120

percent of the prescribed dose. This enforcement discretion will apply if the licensee used

absorbed dose to compare the dose delivered to the treatment site with the prescribed dose;

doses to normal tissues and structures do not exceed the regulatory dose thresholds for

reporting MEs in current section 35.3045(a)(3); and the total dose for the treatment site was

expressed in the WD as absorbed dose. This additional regulatory relief is being offered

because variables in post-implant dosimetry studies cause calculated absorbed dose to be an

unreliable metric for regulatory purposes.

This regulatory relief does not pose a safety concern because the permanent implant therapies

planned by many practitioners have as their objective delivering as much radiation dose as

possible to the treatment site without exceeding medically-recognized dose limits for nearby

normal tissues and structures, i.e., organs at risk.

Also, the NRC recognizes that the current ME reporting of delivered total dose to the treatment

site exceeding 120 percent, compared to the prescribed dose, inappropriately limits the medical

practitioners ability to provide optimum medical care and treatment to his/her patients by

maximizing the delivered total dose to the treatment site. Note that the revisions to 10 CFR 35.3045 that are now under development for permanent implant brachytherapy would eliminate

all treatment site dose variance threshold criteria present in the current 10 CFR 35.3045 ME

reporting requirements.

This enforcement discretion for treatment site total dose exceeding 120 percent of the

prescribed dose will not apply if the total dose for the treatment site was expressed in the written

directive as total source strength and exposure time.

RIS 2013-10

Page 6 of 7

This is because licensees have more control over delivery of the prescribed dose when using

source strength and exposure time. This policy does not change the physicians current ability to

make intraoperative adjustments in the quantity of source strength implanted based on the

conditions encountered during the surgical procedure and to document such adjustments in the

portion of the written directive required after implantation but before completion of the

procedure.

This policy does not provide enforcement discretion for a delivered dose to the treatment site

that is less than 80 percent of the intended dose, the lower limit for treatment site dose variance

in the current section 35.3045(a)(1)(i). The intent of permanent implant brachytherapy is to

deliver at least a minimum dose in accordance with the physicians direction; therefore,

exercising enforcement discretion for an underdose would not further this intent.

BACKFIT DISCUSSION

This RIS requires no action or written response. Any action on the part of addressees in

accordance with the guidance contained in this RIS is strictly voluntary and, therefore, is not a

backfit under any regulatory requirement. Consequently, the staff did not perform a backfit

analysis.

FEDERAL REGISTER NOTIFICATION

A notice of opportunity for public comment on this RIS was not published in the Federal Register

because this RIS is informational and does not represent a departure from current regulatory

requirements.

CONGRESSIONAL REVIEW ACT

This RIS is not a rule as defined in the Congressional Review Act (5 U.S.C. §§ 801-808).

PAPERWORK REDUCTION ACT STATEMENT

This RIS references information collection requirements that are subject to the Paperwork

Reduction Act of 1995 (44 U.S.C. 3501 et seq.). These information collection requirements

were approved by the Office of Management and Budget, approval number 3150-0010.

PUBLIC PROTECTION NOTIFICATION

The NRC may not conduct or sponsor, and a person is not required to respond to, a request for

information or an information collection requirement unless the requesting document displays a

currently valid OMB control number.

RIS 2013-10

Page 7 of 7

CONTACT

This RIS requires no specific action or written response. Please direct any questions to the

technical contact listed below or the appropriate regional office.

/RA PHenderson for/

Brian J. McDermott, Director

Division of Materials Safety and State Agreements

Office of Federal and State Materials

and Environmental Management Programs

Technical Contact: Ronald Zelac, Ph.D., FSME

(301) 415-7635

Email: Ronald.Zelac@nrc.gov

Enclosures:

1. Appendix B - Inspection Procedure 87132

2. Appendix C - Inspection Procedure 87132

3. Interim Enforcement Policy

4. FSME Generic Communications

RIS 2013-10

Page 7 of 7

CONTACT

This RIS requires no specific action or written response. Please direct any questions to the

technical contact listed below or the appropriate regional office.

/RA PHenderson for/

Brian J. McDermott, Director

Division of Materials Safety and State Agreements

Office of Federal and State Materials

and Environmental Management Programs

Technical Contact: Ronald Zelac, Ph.D., FSME

(301) 415-7635

Email: Ronald.Zelac@nrc.gov

Enclosures:

1. Appendix B - Inspection Procedure 87132

2. Appendix C - Inspection Procedure 87132

3. Interim Enforcement Policy

4. FSME Generic Communications

DISTRIBUTION: WITS 201200139 EDATS-SECY-2012-0415

MSSA r/f

ML13156A195

OFFICE MSSA/RMSB MSSA/RMSB MSSA/RMSB MSSA/RMSB OE

NAME RZelac SGabriel AMcIntosh SGabriel for NHilton

CEinberg

DATE 6/4/13 6/19/13 6/13/13 6/19/13 7/2/13

OFFICE OIS OGC-NLO OGC-CRA MSSA MSSA

NAME TDonnell BJones JAdler for PHenderson PHenderson

BAmmon for BMcDermott

DATE 7/10/13 7/23/13 7/23/13 7/30/13 7/30/13

OFFICIAL RECORD COPY