Repeat prostate biopsy and the incremental risk of clinically insignificant prostate cancer

Abstract

Objectives: To determine the incremental risk of diagnosis of clinically insignificant prostate cancer with serial prostate biopsies.

Methods: We reviewed our institutional radical prostatectomy (RP) database comprising 2411 consecutive patients undergoing RP. We then stratified patients by the prostate biopsy on which their cancer was diagnosed and correlated biopsy number with the risk of clinically insignificant disease and adverse pathology at radical prostatectomy.

Results: A total of 1867 (77.4%), 281 (11.9%), and 175 (7.3%) patients underwent 1, 2, and 3 or more prostate biopsies, respectively, before RP. Increasing number of prostate biopsies was associated with increasing prostate volume (P <.01), prostate-specific antigen (P <.01), associated prostate intraepithelial neoplasia (P <.01), and increased likelihood of clinical Gleason 6 or less disease (P <.01). On pathologic analysis, increasing number of prostate biopsies was associated with increased risk of low-volume (P <.01), organ-confined (P <.01) disease. The risk of clinically insignificant disease was found to be 31.1%, 43.8%, and 46.8% in those undergoing 1, 2, and 3+ prostate biopsies, respectively. Conversely, the risk of adverse pathology was found to be 64.6%, 53.0%, and 52.0% in those undergoing 1, 2, and 3+ prostate biopsies, respectively.

Conclusions: Patients undergoing multiple prostate biopsies before RP are more likely to harbor clinically insignificant prostate cancer than those who only undergo 1 biopsy before resection. Nonetheless, the risk of adverse pathology in patients undergoing serial biopsies remains significant. The increased risk of prostate cancer overdiagnosis and overtreatment must be balanced with the continued risk of clinically significant disease when counseling patients regarding serial biopsies.