The natural course of low grade, non-metastatic prostatic carcinoma.

A surveillance study was carried out on 167 patients with low grade, low stage prostatic carcinoma without known metastases; of these, 146 were evaluated, the mean follow-up time being 50 months. Local tumour progression occurred in 77 patients (53%), corresponding to a 5-year cumulative probability of progression of 67%. Ten patients developed metastases, 5 died of prostatic carcinoma and 24 died of other causes. Cox's regression analysis showed that the initial cytological grade of the tumour was of prognostic importance, but initial local tumour stage, prostatic acid phosphatase activity and age had no statistically significant prognostic value. Although the number of patients developing metastases and dying of prostatic carcinoma was low, most tumours seemed to progress locally.