High yield of saturation prostate biopsy for patients with previous negative biopsies and small prostates

Men with previously negative prostate biopsies but continued suspicion for carcinoma present a diagnostic dilemma often managed by saturation prostate biopsy (SPB). We sought to determine the patient characteristics for which repeat biopsy by SPB provides the greatest utility for prostate cancer detection.

The records of the men at the state hospital and affiliated Veterans Affairs Medical Center with previously negative prostate biopsy findings who had then undergone SPB were reviewed. The predictors of cancer were analyzed, and those that were significant were included in a multivariate logistic regression model.

A total of 82 men underwent SPB from November 2001 to March 2006. Their mean age was 61 years (range 43 to 76), and 44 (54%) were white, 37 (45%) were African American, and 1 (1%) was Asian. The mean prostate-specific antigen level at SPB was 9.1 ng/mL (range 1.0 to 34). The number of prior biopsies was one in 43 patients (52%) and two or more in 39 patients (47%). The prostate volume averaged 53 cm(3) (range 12 to 200). SPB included a median of 24 cores (range 24 to 40). Of the 82 patients, 16 (19.5%) were diagnosed with cancer, of whom 10 (63%) elected to undergo radical prostatectomy. The only significant predictors of prostate cancer were the prostate-specific antigen level (P = 0.009) and prostate volume. The cancer detection rate was 57% for patients with a prostate volume less than 37 cm(3) and 7% for those with larger glands, and the difference was significant on multivariate analysis (odds ratio 31, 95% confidence interval 6 to 158, P <0.0001).

The results of our study have shown that SPB is an effective diagnostic tool with a high yield for men with persistent suspicion for prostate cancer, prior negative biopsy findings, and a prostate volume less than 37 cm(3).