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

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%.