Incidental carcinoma of the prostate: an analysis of the predictors of progression.

Incidentally discovered prostatic cancer can pursue a benign clinical course or it can rapidly progress. Differentiating those tumors with low biological potential from more aggressive lesions has been the focus of many reports. To define more completely the variables that can be used to predict those patients with low biological potential requiring limited treatment from those needing more extensive therapy, a retrospective study of 232 patients with incidentally discovered cancer was undertaken. Progressive disease was used as an endpoint for statistical analysis with the Kaplan-Meier technique and Cox's multiple hazard regression mode. This extensive analysis of multiple parameters demonstrated a significant advantage of survival free of disease for patients presenting with tumors manifesting a lower Gleason score and volume extent. Probability tables were constructed to allow for prediction of the probability of progression for a given patient with incidentally discovered prostate cancer directly related to patient age at diagnosis, Gleason score, and initial volume extent of the tumor. With these tables a logical therapeutic approach can be derived for each patient in an attempt to maximize survival free of disease with minimal intervention.