[Significance of transrectal hyperthermia in the treatment of benign prostatic hyperplasia]

Though the local hyperthermia for the management of benign prostatic hyperplasia has drawn much attention as one non-surgical treatment, no definite conclusion could yet be obtained in terms of the efficacy. In this study local hyperthermia was induced in evaluable 33 cases with benign prostatic hyperplasia using Primus, and the effectiveness of this modality of treatment was investigated by analysing the subjective and objective response following hyperthermia. The prostate was heated trans-rectally up to 43 degrees C with 915 MHz microwave for one hour. Hyperthermia was carried out twice a week for ten times for the sake of thermotolerance. Urinary obstructive symptoms were divided into diurnal and nocturnal frequency, urinary urgency, the degree of urinary stream, hesitancy and dribbling. Each symptom was described before and after the treatment according to the scoring system. Moreover, objective changes of urinary flow and prostatic size were estimated by the residual urine volume, uro-flowmetry, rectal palpation of the prostate and echography. Hyperthermic treatment improved urinary flow markedly, but no appreciable alteration could be observed as to the size of the prostate. The overall efficacy, including subjective and objective response, could be summarized as 37% of effectiveness, and 33% of slight effectiveness, that is, 70% of effective ratio. As to the side effect, anal pain was noted in few cases of the present series. Therefore, transrectal hyperthermia may be a suitable modality for non-surgical treatment of benign prostatic hyperplasia.