Clinicopathological characteristics of prostatic adenocarcinoma in men with atypical prostate needle biopsies

PURPOSE: Atypical or nondefinitive diagnoses comprise 1.5 to 10% of all prostate needle biopsies and many men with atypical biopsy have carcinoma on rebiopsy. We characterize the clinical and pathological features of these men and the tumors, and compare them to those of other men who had more than 1 biopsy. MATERIALS AND METHODS: All prostate needle biopsies done at our institution between 1989 and 1996 on men with a followup biopsy were reviewed and the clinicopathological features were correlated. RESULTS: A total of 343 men had more than 1 biopsy during this period. Of the biopsies 64 were atypical and followup (repeat biopsy) was available for 59. Men with an atypical diagnosis were more likely to have carcinoma (34%) and to be diagnosed subsequently earlier (270 days) than those with an initial negative diagnosis (22%, 603 days). No significant differences were noted in patient age, results of digital rectal examination, initial or followup serum prostate specific antigen, subsequently identified tumor size or Gleason score on needle biopsy or at resection. Although on review as many as 38% of the original atypical foci could be reclassified, this reclassification did not significantly change the results of rebiopsy. CONCLUSIONS: Men with an atypical diagnosis on prostate biopsy are significantly more likely to have carcinoma on rebiopsy than men with an initial negative diagnosis, and the second biopsy should be performed at a significantly shorter interval. The tumors that are subsequently identified in these men are similar to those identified in men without an atypical biopsy.