Analysis of External Radiotherapy for Localized Prostatic Cancer

From 1968 to 1986, 62 patients with Stage C prostatic cancer were treated at Hiroshima University Hospital. Of these, 33 patients were treated by castration plus DES-DP (hormone therapy alone) from 1968 to 1975. Twenty-nine patients were treated by definitive radiotherapy after castration (combined therapy) from 1976 to 1986. Although the expected survivals of both periods were comparable, the survival rate of the combined therapy group was significantly higher than that of hormone therapy-alone group (five-year; 78.3% vs. 46.9% and ten-year; 52.2% vs. 0%, p < 0.05). Eight of the 29 patients in the combined therapy group died. Four died of prostatic cancer and four of other diseases. Total dose was 6000 cGy or less in the former four, while 19 of the 29 patients (66%) received greater than 6000 cGy. Acute complications during radiation were observed in 18 of the 29 patients (62%). In only one case, however, irradiation was interrupted because of acute complications. Late complications, observed six months or more after the end of irradiation and required admission to the hospital for diagnosis or treatment, were developed in four of the 29 patients (14%). They were contracted bladder, perforation of the rectum, bladder neck contracture and ileus. Patients with ileus and contracted bladder each had history of laparotomy and vesical stone, respectively. As to portals and total dose of these four, anterior-posterior parallel opposing portals only was conducted in all and total dose was less than 6000 cGy in three of them. The results of this study revealed the superiority of the combined therapy over hormone therapy alone for treating Stage C prostatic cancer, and also showed the optimum total dose and portals.