[PSA bounce after brachytherapy with permanent seed implantation for prostate cancer].

ABSTRACT

PURPOSE: To evaluate prostate specific antigen (PSA) bounce that may occur as a time PSA rise phenomenon during follow up period after brachytherapy (BT) with permanent seed implantation for prostate cancer. (Materials and methods) Seven hundred and forty-six patients had undergone BT from November 2003 to April 2007 in a single institute, and of 130 patients who did not receive hormone therapy and had minimal 3-year follow up are analyzed. PSA bounce was defined as a rise of at least 0.4 ng/ml with spontaneous return to pre-bounce level or lower. RESULT: Among the 130 patients, 40 patients (30.8%) developed PSA bounce, and median time to PSA bounce was 18 months after the BT. With univariate analysis, younger patients (P = 0.027) and larger prostate (P = 0.030) had statistically significant correlation with PSA bounce. With multivariate analysis, younger patients were identified as only independent factor for predicting PSA bounce. Eight patients out of 130 patients (6.2%) triggered the Phoenix definition (nadir + 2 ng/ml) of PSA failure, however, clinical failure was seen only in 3 patients, and other 5 patients were considered as PSA bounce. CONCLUSION: PSA bounce is likely to occur in younger patients within 3 years after BT. It is clinically important to distinguish PSA bounce from PSA failure during following period after BT.