[Clinical and analytical parameters that might indicate a second biopsy in patient with high PSA and previously negative biopsy]. / Parámetros clínicos y analíticos que indicarían la realización de una segunda biopsia en pacientes con PSAelevado y biopsia previa negativa.

OBJECTIVES: To determine what clinical, analytic and ultrasound parameters, are more effective to predict the result of a second biopsy in patient with high PSA and a first prostate biopsy negative. MATERIAL AND METHODS: It was carried out a longitudinal study in a series of 435 cases with negative prostate biopsy. In 59 of these cases it was practiced a second biopsy due to a permanent or sudden high PSA levels with or without a suspicious digital rectal examination. Of the 31 cases with a negative second biopsy, in 4 cases it was carried out a third biopsy. The biopsy was made in all the occasions by transrectal ultrasound guided sextant biopsy. It were also valued the ultrasound characteristic of the prostate, the prostate volume and the proportion of free PSA. RESULTS: It was demonstrated statistically significant differences among the patients with a second biopsy negative and positive regarding: the age, proportion of free PSA, abnormal digital rectal examination and presence of hipoechogenic areas in the prostate. The multivariate analysis demonstrated that the only significant parameters were the proportion of free PSA and the existence of an abnormal digital rectal examination. Based on the data of multivariate analysis, we settled down for the patients with normal digital rectal examination a cut-off point of 0.23 of proportion of free PSA as indication for the realization of a second biopsy, and of 0.59 for the patients with abnormal digital rectal examination. This protocol applied to our series would avoid the realization of a second biopsy in 8 patients, and a third biopsy in 1 patient, diagnosing all the cases of prostate cancer. CONCLUSIONS: The digital rectal examination associated with the proportion of free PSA constitutes a reliable parameter to indicate the realization of a second prostate biopsy in patient with high PSA and previous negative biopsy.