Incidence of Clinically Significant Prostate Cancer After a Diagnosis of Atypical Small Acinar Proliferation, High-grade Prostatic Intraepithelial Neoplasia, or Benign Tissue

To assess the incidence of clinically significant and insignificant prostate cancer after an initial biopsy that revealed either atypical small acinar proliferation (ASAP), high-grade prostatic intraepithelial neoplasia (HGPIN), or benign tissue. We retrospectively identified patients diagnosed with ASAP, HGPIN, or benign tissue who had a repeat prostate biopsy within 1 year of diagnosis during 1987-2015. We compared the incidence of any prostate cancer and clinically significant prostate cancer (based on Gleason score, prostate-specific antigen (PSA), number of positive cores, and core volume) for each diagnostic group. A total of 17,016 biopsies were performed in 12,817 patients during 1987-2015. Among the 615 patients who had a repeat biopsy within 1 year of their first, 261 (42.4%), 208 (33.8%), and 146 (23.8%) had ASAP, HGPIN, or benign tissue on the initial biopsy, respectively. The second biopsy demonstrated significant differences in prostate cancer detection rates between these 3 groups (34.1%, 20.2%, and 15.8%, respectively; P