Correlation of radiotherapeutic parameters and treatment related morbidity in carcinoma of the prostate--analysis of RTOG study 75-06.
Treatment related morbidity, recorded in patients entered onto a RTOG phase III study (testing the value of periaortic irradiation in locally advanced carcinoma of the prostate), has been correlated with radiotherapeutic parameters to identify and quantify the relationship with treatment volumes, doses, and techniques. Between 1976 and 1983 a total of 526 analyzable cases were entered onto the study. The study design entailed randomization to either pelvic irradiation followed by a prostate boost or pelvic and periaortic irradiation followed by a prostate boost. Periaortic irradiation was not associated with a significantly increased incidence of bowel injuries manifested by diarrhea. No correlation between the total dose to the regional lymphatics (ranging from 4400 to 5100 cGy) and the incidence of bowel and bladder injuries could be established. Doses to the prostate in excess of 7000 cGy have not resulted in a significantly increased incidence of bladder injuries, but have been associated with a significant increase in the incidence of bowel injuries manifested by diarrhea. The techniques of pelvic irradiation did not seem to significantly influence the incidence of bowel or bladder complications. The technique of delivery of the prostatic boost did seem to influence the incidence of bowel injuries. This refers to the lateral boost technique and the perineal boost technique which have been associated with a higher incidence of diarrhea. All of the conclusions based on this analysis are applicable only to treatment volumes and dose ranges used in this study and to conventional fractionation of 180 to 200 cGy per day.
D003556:Cystitis / Q000209:etiology; D003967:Diarrhea / Q000209:etiology; D006471:Gastrointestinal Hemorrhage / Q000209:etiology; D006417:Hematuria / Q000209:etiology; D006801:Humans; D008297:Male; D011349:Proctitis / Q000209:etiology; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011878:Radiotherapy / Q000009:adverse effects*; D012007:Rectum; D014525:Urethral Stricture / Q000209:etiology