Low AUA symptom score independently predicts positive prostate needle biopsy: results from a racially diverse series of 411 patients.

OBJECTIVES: To evaluate the prebiopsy parameters, including the American Urological Association symptom score (AUASS), that may be predictive of positive biopsy. Transrectal ultrasound (TRUS) biopsy of the prostate represents the reference standard in the diagnosis of prostate cancer.

METHODS: A total of 411 consecutive men undergoing TRUS biopsy were prospectively evaluated. The indications for biopsy were abnormal digital rectal examination (DRE) findings and/or an elevated prostate-specific antigen (PSA) level. A single surgeon (C.R.P.) examined all the men. DRE and TRUS were each given a level of suspicion between 1 (low suspicion--smooth DRE, homogeneous TRUS) and 5 (high suspicion--hard DRE, hypoechoic lesion). A level of suspicion of 3 or greater was considered abnormal. The prebiopsy parameters examined included PSA level, age, race, biopsy history, prostate volume, TRUS-detected lesion, and AUASS.

RESULTS: Of 411 men, 62% were African American and 38% were white. The mean PSA level was 11.6 ng/mL. The mean patient age was 65.3 years. Overall, 39% of men had abnormal DRE and 32% abnormal TRUS findings. The mean AUASS was 9.3. The positive biopsy rate was 40.8%. Univariate analysis demonstrated that age, PSA level, prostate volume, abnormal DRE findings, TRUS-detected lesion, and AUASS (less than 7, low) were all predictive of a positive biopsy (P <0.05). Race was not statistically significant (P = 0.38). Detailed analysis of the AUASS in the 411 men indicated that 41% had low symptom scores (less than 7), 32% had moderate scores (8 to 19), and 27% had severe scores (20 to 35). In the group of men with low symptom scores (n = 169), univariate analysis demonstrated that age, PSA level, prostate volume, and abnormal TRUS findings were all statistically significant predictors of positive biopsy (P <0.05). Multivariate analysis of the data from the 411 men demonstrated that age, PSA level, prostate volume, abnormal DRE findings, and low AUASS were all independent predictors of positive biopsy (P <0.05).

CONCLUSIONS: In this prospective study, the independent predictors of positive TRUS biopsy included age, PSA level, prostate volume, abnormal DRE findings, and low AUASS. A low AUASS may be an important variable to consider when counseling patients before biopsy and when designing patient algorithms for prostate biopsy.