[Determining factors in the presence of carcinoma in prostate biopsies]

Prostate biopsy is the diagnostic method to detect prostate carcinoma. We try to identify the optimal PSA cut-off, biopsy indication and the clinico-pathological characteristics in order to differentiate those patients with negative biopsy in which we should repeat the proceeding.

We study 344 biopsies in 292 patients for 16 months. An univariate and multivariate study to identify the influent factors in the existence of prostate cancer in the first biopsy and in the patients with a second one was taken place.

Patients in the first biopsy Univariate study: Out of these variables (PSA, PSA ratio, digital rectal examination and prostate volume) just the PSA has statistical significance. Multivariate study: Only the the PSA is an indepent influence factor. Receiving Operated Curve: The optimal cut-off is 10.5 ng/ml. Patients with a second biopsy Univariate study: None of the variables is related with the existence of prostate cancer. Groups comparison: A comparison between the patients in the first biopsy and the patients with a second biopsy is performance with no statistical differences in the variables already mentioned.

The patient with a PSA greater than 4 ng/ml should be perform a prostate biopsy, mostly if his PSA is over 10 ng/ml. In our experience we do not related the need of a second biopsy with any factor in particular, therefore in our opinion and because of the high rate of negative false, all of the patients should be controlled and undergo a second biopsy if any change in PSA or clinics modification takes place.