[Relation of age and prostatic volume to cancer detection in prostatic biopsies from patients with non-suspect rectal palpation]

To evaluate which clinical variables are predictive for prostate cancer and possible relationships among them, in patients with elevated PSA and non suspicious digital rectal examination (DRE) undergoing first prostate biopsy.

1618 patients with elevated PSA and non suspicious DRE who underwent sextant peripheral prostate biopsy were selected from our database. PSA, age, prostate volume, and detectable nodule by ultrasound were selected as variables related to cancer detection in first and second biopsies.

Mean age was 67.5 +/- 7.4 (37-88) years, mean PSA was 16.9 +/- 116.5 (3.6-4500) ng\ml, mean prostate volume was 65.7 +/- 37.8 (8-352) cc. 23.3% patients presented a hypoechoic nodule within the peripheral zone of the gland. 18.8% presented prostate cancer on first biopsy. On multivariate analysis, age (p < 0.001), prostate volume (p < 0.001), and presence of a nodule on ultrasound (p = 0.003) were considered independent predictive variables for cancer detection on biopsy. Direct relationship with age, and inverse relationship with prostate volume were shown. Detection rates on second biopsy were greater in patients with prostates = 40 cc in comparison to those > 40 cc (p = 0.02). First two biopsies detected 95% of cancer cases, first three up to 98%.

Age and prostate volume should be taken into consideration when individualizing the number of cores to obtain at the time of biopsy. The efficacy of peripheral sextant biopsy in prostates = for 40 cc should be re-evaluated. Third and fourth biopsies should be reserved for patients with very adverse risk factors.