Is a single focus of low-grade prostate cancer diagnosed on saturation biopsy predictive of clinically insignificant cancer?

Abstract

Objectives: To evaluate the incidence of indolent prostate cancer (PCa; <0.5 ml cancer and Gleason score, GS, <or=6) in men with microfocal PCa diagnosed on saturation biopsy (SPBx) submitted to radical retropubic prostatectomy.

Methods: From January 2005 to December 2008, 413 patients (median age 61.5 years) underwent SPBx (median 30 cores). A single neoplastic microfocus (5% or less of cancer in a single core) was found in 55 men and all patients underwent retropubic prostatectomy. Median PSA was equal to 8.2 ng/ml, digital rectal examination was negative and GS was 6 in 40 cases and not evaluable in 15 cases.

Results: Prostatectomy specimens showed a significant cancer in 48/55 (87.3%) patients with a median GS of 6.2 (range 5-8), presence of extraprostatic extension and positive surgical margins in 15 (27.3%) and 8 (14.5%) cases, respectively. Six patients had an indolent PCa, and in 1 case no tumor was found.

Conclusions: Patients with a single microfocal PCa diagnosed on SPBx corresponded to an insignificant cancer in surgical specimens only in 12.7% of cases, but they should be informed that they may harbor more aggressive disease with a risk of non-organ-confined cancer that in our series was 27.3%.