Tissue PSA is the best predicting variable for the outcome of endocrine treatment of prostatic carcinoma

In order to evaluate the prognostic value of tissue-PSA (prostatic-specific protein, measured in aspiration biopsies) 231 hormonally treated patients with verified carcinoma of the prostate (CaP) but without metastasis were studied retrospectively. T-PSA was determined at the time of diagnosis in all patients and in 52 of these also at 6, 12 and 24 months after diagnosis. Of the 231 patients, 79 died of prostatic carcinoma and 152 were still alive or had died of other diseases at the end of the observation period (more than 71 months). In a first set of evaluations the predictive value of a single analysis at the time of diagnosis was studied in 179 patients. It was found that tissue PSA was the most important factor for predicting both time to progression and time to death in CaP. Other competing factors were S-PSA, free S-PSA, age, clinical stage, grade and DNA-ploidy. Further evaluations regarding serial PSA determinations were performed in 52 patients. Tissue PSA increased during treatment in all patients who died of CaP. In all patients who survived or died for other reasons, tissue PSA decreased during treatment and remained low. The change of tissue PSA seen between 0, 6 and 12 months could in all cases predict the clinical outcome. It is concluded that a single analysis of tissue PSA at the time of diagnosis can predict the clinical outcome in most cases and that serial determinations can predict the outcome in almost all cases of a CaP without metastasis at the time of diagnosis. This requires that we use this assay when selecting between patients who will survive on hormonal treatment and those who most probably would benefit from a more aggressive treatment.