Surveillance biopsy and active treatment during active surveillance for low-risk prostate cancer.

Background: The goals of the study were to examine surveillance biopsy and active treatment in patients under active surveillance (AS) for low-risk prostate cancer and to determine the active treatment-free survival rate. Methods: The subjects were 87 patients with low-risk prostate cancer who were under AS between 2000 and 2010. The eligibility criteria for AS were T1c, Gleason score ≤6, prostate-specific antigen level ≤10 ng/ml, one or two positive biopsies, maximum cancer involvement ≤50 %, and age ≤80 years old. Results: Of the 87 patients, 48 underwent the first surveillance biopsy (55.2 %). In this biopsy, no cancer was found in 33.3 % of cases, 27.1 % remained eligible for AS, and 39.6 % did not meet the AS criteria (up-grade 22.9 %, up-volume 16.7 %). A second surveillance-biopsy was performed at 1.9 years after the first biopsy. No cancer was found in 20.0 % of cases, 40.0 % remained eligible for AS, and 40.0 % did not meet the AS criteria (up-grade 26.7 %, up-volume 13.3 %). A total of 50 patients received treatment by 1.7 years after starting AS, mainly due to an up-grade or up-volume. However, some patients underwent radiotherapy despite biopsy results indicating no cancer or eligibility for AS. The active treatment-free survival rate was 64.1 % after 2 years. Conclusions: Surveillance biopsy is important for identifying patients who require active treatment. The results in this study allowed determination of the active treatment-free survival rate and are informative for making treatment decisions. [ABSTRACT FROM AUTHOR]