[Sexual function after permanent seed implant prostate brachytherapy].

Purpose: The aim of this study was to evaluate the long-term effects of permanent seed implant prostate brachytherapy (BT) on sexual function (SF).

Materials And Methods: From September 2003 to July 2005, 56 patients underwent radical retropubic prostatectomy (RRP) without any hormone therapy, while 353 patients had undergone BT without any adjuvant hormone therapy in a single institute. Out of these 353 patients in the BT group, 305 patients received neoadjuvant hormone therapy (BT NHT + group), while 48 did not (BT NHT - group). SF was prospectively evaluated using the UCLA Prostate Cancer Index (UCLA-PCI). Potency was defined as the UCLA-PCI Q26 point of > or = 3.

Result: The preimplant UCLA-PCI scores of SF for BT NHT - and BT NHT + groups were 50.9 and 13.4, respectively. The SF score of the NHT - group post operatively decreased to 38.9 within 6 months, but was maintained at the same level after that. With the recovery of the androgen, SF score of the NHT + group improved after BT: however, it did not reach up to that of the NHT - group. In the univariate analysis, patient's age was the only predictive factor for SF after BT. Thirty-four out of 48 patients in the BT NHT - group and 23 out of 56 patients in the RRP group showed adequate potency before surgery. Their 5-year potency preservation rate was 73.6% in the BT NHT - group and 4.3% in the RRP group.

Conclusion: SF slightly decreased immediately after BT but was usually maintained during the course observation for 5 years. The 5-year SF preservation rate after BT was 73.6%.