[Cancer of the rectum: preoperative radiotherapy (344 cases)]

Radiation therapy prescribed as an adjuvant to surgery is an effective treatment of many cancers but has not been universally accepted for treatment of rectal cancer. Since 1969, preoperative radiation therapy of rectal carcinoma has been proposed in a curative intent, both at Centre Paul Lamarque in Montpellier and at Centre Claudius Regaud in Toulouse, France. Megavoltage radiotherapy was used in all patients and doses ranges from 35 to 40 Gy during 2.5 to 3 weeks. Among the 344 patients treated between 1969 and 1981, the ratio of abdominoperineal excision to anterior resection was 239/105, the percentage of pelvic recurrence was 7,8 per cent, and the 5-year survival rate, including postoperative mortality (5.2%) was 78 per cent in the Centre Claudius Regaud series and 64 per cent in the Centre Paul Lamarque series. The 10-year survival rate was 50 per cent. There was no evidence of an increased morbidity following irradiation. Pathologic staging showed no residual tumour in the excised specimen in 5.2 per cent of the cases. The number of Dukes'C cases was smaller than according to the clinical pre-treatment assessment of the tumours (16%). Ultrasonography of the liver and plasmatic CEA determination avoid irradiation of metastatic patients. Further development of this curative approach should include a postoperative boost of 25 Gy for patients who are at high risk for local failure in the pelvis, and an adjuvant chemotherapy for Dukes'C patients.