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Permanent Interstitial Brachytherapy for the Management of Carcinoma of the
Prostate Gland, Gregory S. Merrick, MD, Kent E. Wallner, MD, and Wayne
M. Butler, PhD, The Journal of Urology, 2003;May;169:1643-1652.
| Type of Study |
Review of published literature. |
| Purpose |
To summarize literature about permanent prostate brachytherapy
including biochemical outcomes, quality of life parameters and areas of
controversy. |
| Issues |
| • |
How effective is brachytherapy for all types of patients? |
| • |
How does brachytherapy impact patients’ quality of life? |
| • |
Do unfounded contraindications exist? |
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| Number of Patients |
Not applicable.
|
| Type of Patients |
Varies by study.
|
| Length of Time
Patients Were Followed |
Varies by study; up to 10 years. |
| Results and/or
Conclusions |
| • |
Brachytherapy can be effective for patients with low-, intermediate- and
high-risk features. |
| • |
Brachytherapy can be an effective treatment regardless of the patient’s age or
size of prostate. |
| • |
Severe urinary and rectal complications are rare. |
| • |
Physician expertise is important to favorable outcomes. |
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In a review of current published literature, the authors examined numerous
brachytherapy issues including outcomes, quality of life and areas of
controversy. The review resulted in the following conclusions.
OUTCOMES RELATED TO RISK FACTORS: Brachytherapy can be effective for patients
with low-, intermediate- and high-risk features.
“Using various planning and intraoperative techniques, the majority of the
brachytherapy literature demonstrates durable biochemical outcomes (cure rates)
for patients with low, intermediate and high risk features.”
Cited survival rates (biochemical disease-free survival) included:
| • |
87-96% after five to 10 years for low-risk patients (Gleason score of 6 or
less, PSA of 10 or less and T1c/T2a staging according to 1997 American Joint
Committee on Cancer (AJCC) criteria). |
| • |
82% after nine years for intermediate-risk patients (Gleason score of 7 or
greater, PSA of 10 or greater, or stage T2b according to 1997 AJCC criteria).
For hormone naïve patients treated with brachytherapy and supplemental external
beam radiation therapy, a 6-year rate of survival of 97% has been reported. |
| • |
76% after five years for high-risk patients (with two or three certain risk
factors including Gleason score of 7 or greater, PSA of 10 or more and/or stage
T2b or greater according to 1997 AJCC criteria) receiving supplemental external
beam radiation therapy, followed by a Pd-103 boost. For hormone naïve patients,
an 80% rate has been reported after six years for patients with certain
characteristics. |
| • |
Not all studies of intermediate- and high-risk cases have shown favorable
results. |
DEBUNKING MYTHS
“Although not all patients are good candidates for brachytherapy, to our
knowledge a reliable set of pretreatment criteria to predict implant-related
morbidity is not available. Most alleged contraindications to brachytherapy
have been propagated with little or no supporting data.”
| • |
AGE: Brachytherapy can be an effective treatment regardless of the patient’s
age. “There has been a reluctance to recommend brachytherapy for
younger patients… Outstanding biochemical outcomes with a plateau on the PSA
control curve have been reported for hormone naïve patients who undergo
brachytherapy who are 62 years or younger.” |
| • |
PROSTATE SIZE: Brachytherapy can be an effective treatment for patients with
large prostate glands, who are often counseled not to receive this type of
treatment.
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| • |
“Contrary to popular perception, groups have reported that appropriately
selected patients with a large prostate can be implanted with acceptable
morbidity.” |
Debunking Additional Myths:
In addition to young patient age and large prostate size, alleged
contraindications to brachytherapy -- generally not supported by clinical
findings -- include pubic arch interference, chronic prostatitis, transurethral
resection of the prostate, obesity, inflammatory bowel disease and adverse
pathological features such as high Gleason score, perineural invasion and
percent positive biopsies.
QUALITY OF LIFE ISSUES (short-term side effects and long-term
complications)
| • |
“Although a reliable set of pretreatment criteria to predict implant related
morbidity is not available, severe urinary and rectal morbidity is rare.” |
| • |
“After brachytherapy almost all patients have some degree of urinary
irritative/obstructive symptomatology with acute urinary retention in 2% to
22%.” (NOTE: According to principal author Dr. Merrick, this figure now ranges
from 2% to 32% and drops to less than 2% after five days.) Drugs are used to
alleviate these symptoms and the timing may substantially influence their
effect. |
| • |
There is a 5% to 12% risk of urethral strictures up to five years
post-treatment, easily managed by dilatation. |
| • |
Rectal complications consist primarily of mild proctitis which usually resolves
spontaneously. |
| • |
Long-term bowel dysfunction is relatively uncommon, although preliminary
results of a randomized trial indicate I-125 implants result in greater rectal
morbidity. |
| • |
Results of studies regarding impotence after brachytherapy vary. In one study,
when those who maintain potency are combined with those who take medication to
restore erectile dysfunction, 92% of men are able to maintain erectile function
six years following brachytherapy. “Erectile dysfunction has been reported in
6% to 90% of patients who undergo brachytherapy,” the journal article noted.
However, it also indicated most patients with brachytherapy-induced erectile
dysfunction respond favorably to sidenafil (medication). “The reported wide
ranges of erectile dysfunction likely reflect the differences in follow-up,
patient selection and the mode of data collection. In the only brachytherapy
series using a patient administered, validated quality of life instrument, 52%
of patients who underwent monotherapy brachytherapy maintained erectile
function at 6 years.” The strongest predictor of erectile dysfunction is the
patient’s functional level before implantation. |
PHYSICIAN EXPERTISE IS IMPORTANT
“It has become increasingly apparent that the efficacy and morbidity depend on
implant quality.”
Principal Investigator: Gregory S. Merrick, M.D., Schiffler Cancer
Center, Wheeling, W.V.
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