What is the fate of repeat biopsies after diagnosis of high grade prostatic intraepithelial neoplasia and atypical small acinar proliferation?

Abstract

In this study, we reviewed the outcomes of patients undergoing repeat biopsies, following initial diagnosis of high grade prostatic intraepithelial neoplasia (HGPIN) or atypical small acinar proliferation (ASAP) and compared the pathological results to second biopsies due to increased PSA. We retrospectively assessed transrectal ultrasound guided prostate biopsy (TRUSBP) database at our institution between January 2003 and March 2011. Nonparametric tests and binary logistic regression analysis was performed. Among the 1451 TRUSBP taken, 30.4%, 6.4%, 4.7% were diagnosed as prostate carcinoma (PCa), HGPIN, ASAP, respectively. Among patients with HGPIN and ASAP, 68 patients and 48 patients with subsequent biopsies were selected. We also selected 128 patients with diagnosis of benign prostatic tissue (BPT) and subsequent biopsies due to increased PSA. After second biopsy, HGPIN and PCa reported in 29.4% and 20.6%, respectively in HGPIN group; ASAP and PCa was reported in 25% and 37.5%, respectively in ASAP group. Significant increase in PCa rate was reported on second biopsy in ASAP group when compares to HGPIN group (37.5% vs 20.6%, p=0.04) and BPT group (37.5% vs 18.8%, p=0.009). Overall, PCa was diagnosed in 26.5%, 45.8%, 18.8% in HGPIN, ASAP, BPT groups, respectively. Significant difference in PCa rate was detected only in ASAP group. PSAD has significant effects on PCa in all groups (p=0.001 and p=0.01, respectively). HGPIN is no longer associated with higher risk of cancer. Patients should be followed with yearly prostate specific antigen (PSA) and digital rectal examination (DRE). Repeat biopsy should be made as soon as feasible in patients with ASAP.