Predictive Factors of Prostate Cancer at Repeat Biopsy in Patients with an Initial Diagnosis of Atypical Small Acinar Proliferation of the Prostate

PURPOSE The factors that predict prostate cancer detection on repeat biopsy were evaluated in patients with atypical small acinar proliferation (ASAP) on the initial biopsy. MATERIALS AND METHODS From 2003 to 2008, 3,130 men with suspected prostate cancer underwent a prostate needle biopsy, and 244 (7.8%) were diagnosed as having ASAP. One hundred seventy of 244 patients were rebiopsied at least once more. They were classified into a prostate cancer group and a noncancer group according to the final pathological diagnosis. The database of rebiopsied patients included age, initial prostate-specific antigen (PSA), PSA density (PSAD), PSA velocity (PSAV), total prostate volume (TPV), and transitional zone volume of the prostate (TZV). We compared differences in the aforementioned parameters between the 2 groups. RESULTS A total of 57 patients (33.5%) with ASAP were ultimately shown to have prostate cancer. Univariate analysis showed that PSAD (p=0.002), PSAV (p=0.001), TPV (p=0.035), and TZV (p=0.005) differed significantly between the cancer and noncancer groups. The results of the multivariate analysis showed that PSAD (p=0.022), PSAV (p<0.001), and TPV (p=0.037) had a statistically significant correlation with cancer detection. CONCLUSIONS PSAD, PSAV, and TPV are predictive factors of prostate cancer in patients with an initial diagnosis of ASAP of the prostate. Although repeat biopsy is mandatory irrespective of PSA values, the follow-up of PSA may help to estimate the probability of cancer in these men.