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Purpose: Prostate brachytherapy sometimes requires the volume receiving >150% of the prescribed dose (V150) to be >50% to obtain satisfactory coverage. There has been concern expressed that high V150 may be associated with higher rates of urinary retention and morbidity., Methods and Materials: We reviewed 207 consecutive cases of prostate brachytherapy treated with palladium 103 ((103)Pd; n = 140) or iodine 125 ((125)I; n = 67). Prescribed doses for (103)Pd monotherapy and boost were 124 and 90 Gy, respectively; for (125)I, the corresponding doses were 160 and 120 Gy. Patients were evaluated at baseline, 1 month, 3 months, and every 6 months thereafter., Results: Median follow-up at the time of analysis was 18 months. For (103)Pd, the mean intraoperative volume and V150 were 30.3 cm(3) and 72%, respectively; corresponding values for (125)I were 38.3 cm(3) and 59%, respectively. Two of the patients treated with iodine and 9 treated with palladium experienced acute urinary retention, which was not statistically significant (P = .48). The rectal V100 for (103)Pd was significantly less than that for (125)I (P < .001). The mean baseline, 1-month, and 12-month American Urologic Association (AUA) scores for (103)Pd were 8.5, 19.7, and 8.2, respectively; for (125)I, the values were 7.4, 17.1, and 13.4, respectively. At 12 months, the AUA scores returned to baseline in the (103)Pd-treated patients, whereas scores in (125)I-treated patients remained elevated (P = .005). High V150 did not appear to cause undue risk of urinary retention or morbidity based on logistic regression analysis of patients treated with monotherapy performed with either isotope., Conclusions: The risk of urinary retention was low, despite high V150 values for both isotopes. In patients treated with brachytherapy alone, no significant increase in urinary morbidity was seen in relation to V150. AUA scores returned to baseline in (103)Pd-treated patients at 1 year, whereas (125)I-treated patients demonstrated continued elevation., (Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.)

Purpose: A report of biochemical outcomes for patients treated with palladium-103 (Pd-103) brachytherapy over a fixed time interval., Methods and Materials: Two hundred thirty patients with clinical stage T1-T2 prostate cancer were treated with Pd-103 brachytherapy and followed with prostate-specific antigen (PSA) determinations. Kaplan-Meier estimates of biochemical failure on the basis of two consecutive elevations of PSA were utilized. Multivariate risk groups were constructed. Aggregate PSA response by time interval was assessed., Results: The overall biochemical control rate achieved at 9 years was 83.5%. Failures were local 3.0%; distant 6.1%; PSA progression only 4.3%. Significant risk factors contributing to failure were serum PSA greater than 10 ng/ml and Gleason sum of 7 or greater. Five-year biochemical control for those exhibiting neither risk factor was 94%; one risk factor, 82%; both risk factors, 65%. When all 1354 PSA determinations obtained for this cohort were considered, the patients with a proportion of PSAs < or = 0.5 ng/ml continued to increase until at least 48 months post-therapy. These data conformed to a median PSA half-life of 96.2 days., Conclusions: Prostate brachytherapy with Pd-103 achieves a high rate of biochemical and clinical control in patients with clinically organ-confined disease. PSA response following brachytherapy with low-dose-rate isotopes is protracted.

The purpose of the study was to determine which clinical parameters might predict individual prostate volume changes from prostate brachytherapy. Fifty consecutive, unselected patients treated at the University of Washington by I-125 or Pd-103 implantation for prostatic carcinoma in 1998 were analyzed. The prostate contours on preimplant transrectal ultrasound (TRUS) images were digitized and the prostate volumes calculated. Postimplant axial CT images of the prostate was obtained at 0.5 cm intervals with patients in the supine position the morning after the implant. The postimplant prostate volume increased by an average factor of 1.7 (+/-0.34) compared with the preimplant volume, the size increase being primarily in the anterior-posterior dimension. The absolute volume change was similar in patients with small vs. large preimplant prostate volume (r = -0.39), but the proportional change was less in patients with a larger prostate volume (r = -0.71). Because patients with a small preimplant prostate had proportionately greater volume increase, their postimplant target coverage was generally less. No single parameter, including preimplant prostate volume, preimplant hormonal deprivation, or supplemental external beam radiation therapy (EBRT) can accurately predict the degree of swelling. The precise significance of and practical solution to implant-related prostate volume changes remains to be determined.