Absence of Lower Urinary Tract Symptoms Is an Independent Predictor for Cancer at Prostate Biopsy, but Prostate-Specific Antigen Is Not: Results from a Prospective Series of 569 Patients

Abstract

Purpose

Prostate needle biopsy (PNB) is the definitive method for the diagnosis of prostate cancer. Our objective was to evaluate prebiopsy parameters, including lower urinary tract symptoms, that may be predictive of positive biopsy.

Patients and Methods

We performed a prospective review of 569 consecutive men who underwent transrectal ultrasound (TRUS)–guided PNB. The prebiopsy variables recorded included age, prostate-specific antigen (PSA) levels, prostate volume (PV), percent free PSA levels, suspicious digital rectal examination (DRE) findings, TRUS-detected lesions, race, and American Urologic Association Symptom Score (AUASS).

Results

Low AUASS, PV, patient age, and abnormal TRUS findings were independent predictors of positive PNB results (P < 0.05). In patients with PSA levels between 4 and 10 ng/mL, the positive predictive value of a low AUASS (< 8) in predicting a positive PNB result is 68.7%. When race was considered (black vs. white), univariate analysis (UVA) indicated that race was a significant predictor (P = 0.034) of positive PNB. A subgroup analysis was performed for black men undergoing PNB (n = 256). Multivariate analysis (MVA) indicates that abnormal TRUS findings; low AUASS, PV, and PSA levels; and absence of prior biopsy are all independent predictors of PNB in the black patient group. A final subgroup analysis (UVA and MVA) was performed for white men (n = 310). Only patient age and PV demonstrated significance as independent predictors of PNBs in this group.

Conclusion

This prospective analysis of 569 men demonstrates that traditional indicators for PNB (abnormal DRE findings and PSA levels) are not significant predictors of prostate cancer. Independent predictors for prostate included age, low AUASS, low PV, and abnormal TRUS findings. A low AUASS (indicative of the absence of benign disease) is an important predictor of prostate cancer.