Development of benign prostatic hypertrophy estimated from ultrasonic measurement with long-term follow up

Sixteen cases of benign prostatic hypertrophy (BPH) were followed up by the measurement of the prostatic weight using transrectal ultrasonotomography over a period of 7 years. In 3 cases (the 'increasing group') the weights increased remarkably, and in the remaining 13 cases (the 'stationary group') did not change very much during the period of observation. The rapid phase of increase in the prostatic weight in the 'increasing group' was observed only in their 6th decade. No special tendency was noticed with regard to age in the 'stationary group'. It is presumed that the enlargement of the hypertrophic prostate might occur rapidly in a short period, probably a few years in the 6th decade or before, and that after rapid enlargement, the weight of the prostate does not change very much.