Prognosis and prostatic volume changes during endocrine management of prostate cancer: a longitudinal study.

A total of 102 patients with histologically proved prostate cancer was followed by transrectal ultrasonography to determine the volume of the prostate during endocrine treatment. The mean volume reduction of the prostate at 3 months after start of treatment was 37.1%, and it was greater in patients treated by orchiectomy (42.1%) compared to those treated by luteinizing hormone-releasing hormone (30.5%). Without consideration of other factors, patients in whom the volume of the prostate had regressed 50% or more at 3 months had a better prognosis (overall survival, intercurrent death corrected survival and survival without distant progression) compared to those with a smaller volume reduction. However, when adjusted for the 2 most important prognostic factors in this study, histological grade and M category, no benefit from a greater prostate reduction as shown by ultrasound could be demonstrated. Similar results applied to the ultrasound findings at month 6. In 24 of the 102 patients an increase of prostatic volume by more than 20% was found after a median interval of 18 months, which was considered local progression. During the observation period systemic progression was encountered in 61 patients. When local progression was observed, the rate of subsequent distant progression was increased by a factor of 2.7, irrespective of grade and M category.