Perma
Permanent Brachytherapy
Medical Events: Experiences of
Pennsylvania
Frank Costello
Organization of Agreement States
August 28, 2012
Milwaukee, Wisconsin
Prostate Seed Implants
• Permanent placement of radioactive seeds
directly into the prostate gland
• Seeds are tiny welded titanium canisters
• Primarily I-125, Cs-131, and Pd-103
Prostate Implant
Image Guided Seed Implantation Using Trans-rectal Ultrasound
Seed Implantation
What are the Rules?
• 10 CFR 35.40 – Written Directives
• 10 CFR 35.41 – Procedures
 Replaced QM Rule
• 10 CFR 35.3045 – Medical Events
10 CFR 35.40 Written Directives
• AU Signature, Date, & Patient Name
• Before Implantation
 Radionuclide
 Treatment Site
 Dose
• After Implantation
 Radionuclide
 Treatment site
 Number of sources and total strength
 Exposure time or total dose
10 CFR 35.41 Procedures
• Licensee shall develop, implement, and maintain
written procedures to provide high confidence:
 Patient identity verified before administration
 Administration in accordance with WD
 Check Computer and Manual Dose
Calculations
 Verify computer dose calculations correctly
transferred to therapeutic medical unit console
10 CFR 35.41 Procedures
• Trained and qualified personnel
• Appropriate equipment and treatment
planning systems, e.g. VariSeed program
• Image guided procedures
• Post Treatment Fluoroscopy
• 30 Day CT
10 CFR 35.3045 Medical Events
Dose differs from prescribed dose
 5 rem Effective Dose Equivalent
 50 rem to an organ or tissue
 50 rem Shallow Dose Equivalent, AND
Total dose differs from prescribed dose by 20% or more
AND/OR
Dose to other than Treatment Site*
>50 rem to organ or tissue
>50% of expected dose
*Excluding permanent implant seeds that were implanted correctly, but migrated outside
the treatment site
Variables affect delivered dose
• Changes in anatomy from pre-planning to implant
date to post-implant CT or MRI date (shrinkage
from hormone treatment, swelling/shrinkage
from tissue trauma).
• Differences in image contrast mechanisms cause
prostate to appear differently on ultrasound vs. CT
vs. MRI.
• Seed migration.
• As a result, post-implant dosimetry calculations
are estimates rather than precise determinations
of delivered dose.
PA Permanent Brachytherapy Events
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Date: June 11, 2009 (not reported)
Licensee A
Prescribed Dose: 145 gray
Administered Dose: 92 gray
Comment: Patient sent to another cancer
center for additional brachytherapy treatment
to “cold spots” in prostate. Licensee then
changed process (Foley catheter bulb).
PA Permanent Brachytherapy Events
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Date: October 5, 2009 (not reported)
Licensee B
Prescribed Dose: 144 gray
Administered Dose: 81.96 gray
Comment: Unreported because it was an
underdose and licensee completed treatment
with external-beam therapy.
PA Permanent Brachytherapy Events
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Date: January 21, 2010 (reported)
Licensee A
Prescribed Dose: 145 gray
Administered Dose: 0.5 gray
Comment: No seeds were placed in prostate.
Penile bulb received 161 gray. Doctor’s
unfamiliarity with new ultrasound unit may
have contributed to event.
PA Permanent Brachytherapy Events
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Date: November 2, 2010 (reported)
Licensee C
Prescribed Dose: 85 gray
Administered Dose: 114 gray
Comment: Incorrect dose was entered into
the VariSeed program. Licensee did not
compare written directive with printed
treatment plan.
PA Permanent Brachytherapy Events
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Date: January 20, 2012 (reported)
Licensee D
Prescribed Dose: 110 gray
Administered Dose: 75 gray
Comment: Possibly caused by prostate edema
So, What are the Lessons Learned?
Understand that the
determination of medical
events for prostate
brachytherapy is difficult. D90
isn’t the sole consideration.
So, What are the Lessons Learned?
Under the current rule,
licensees in good faith may
struggle to know if a given
event is reportable.
So, What are the Lessons Learned?
Inspection Techniques
 Ask if there have been any medical events?
 Spot check the 35.41 procedures
 How would the licensee identify a medical
event?
 Review a sample of written directives
 Talk to RSO, medical physicist, radiation
oncologist, etc.
So, what are the Lessons Learned?
• Medical staff may take position that ultrasound
guided implants may meet 10 CFR 35.41
requirement to provide high confidence that
treatment is IAW Treatment Plan/WD, and that
a 30 day CT not necessary.
• Patients may not return for 30 day CT due to
long distance or lack of motivation.
So, What are the Lessons Learned?
If you identify cases
 Where the D90 is less than 80% of the
prescribed dose, and/or,
 Where less than 80% of the seeds are
inside the prostate
Collect the data and bring it back to the office
for further review.
Current Rulemaking
• Rulemaking on permanent implant
brachytherapy has been in progress for a
long time.
• Included in current ongoing Part 35
rulemaking.
• Dose-based rule? Activity-based rule?
Combination?
• Hard to achieve consensus.
Modest Suggestions
• Recognize that licensees have a day to make
this report after identifying a medical event.
• Avoid notification of patients when their
treatment was actually acceptable.
• Create rule that is clear, unambiguous, and
acknowledged by the medical community
as identifying unacceptable treatments.
• New rule does not have to be consistent
with the conclusions of the VA-Philadelphia
inspection and enforcement action.
Looking to the Future…
• Similar issues have been identified in PA
associated with the use of microspheres in
radiation therapy.
• Future presentation…
Questions?
Frank Costello
DEP Radiation Health Physicist
fcostello@pa.gov
www.depweb.state.pa.us
484-250-5833