Permanent prostate brachytherapy using high V150.

Area of Science:

• Oncology
• Radiation Oncology
• Urology

Background:

• Prostate brachytherapy aims for satisfactory tumor coverage, sometimes requiring high V150 (volume receiving >150% of prescribed dose).
• Concerns exist regarding potential associations between high V150 and increased urinary retention and morbidity.

Purpose of the Study:

• To evaluate the relationship between high V150 and the risk of urinary retention and morbidity in prostate brachytherapy.
• To compare outcomes between palladium-103 ((103)Pd) and iodine-125 ((125)I) brachytherapy.

Main Methods:

• Retrospective review of 207 prostate brachytherapy cases treated with (103)Pd (n=140) or (125)I (n=67).
• Patients were assessed at baseline and at multiple follow-up intervals.
• Analysis included V150, urinary retention rates, and American Urologic Association (AUA) scores.

Main Results:

• High V150 values were observed for both isotopes (72% for (103)Pd, 59% for (125)I).
• No statistically significant difference in acute urinary retention rates between (103)Pd and (125)I groups.
• AUA scores returned to baseline by 12 months for (103)Pd patients, but remained elevated for (125)I patients (P=.005).

Conclusions:

• High V150 in prostate brachytherapy did not correlate with increased risk of urinary retention or morbidity.
• (103)Pd brachytherapy demonstrated superior long-term urinary symptom recovery compared to (125)I.
• The risk of urinary retention was low for both isotopes despite high V150.