New prospects in the conservative treatment of rectal cancer.

Conservative treatment of rectal cancer is applicable only to limited tumors that are assumed to have no lymphatic spread; these are well or moderately well differentiated adenocarcinomas confined to the bowel wall, without palpable pararectal metastatic lymph nodes. The experience of intracavitary irradiation (contact x-ray therapy often combined with iridium 192 implant), based on 245 patients followed for more than five years, shows a low rate of local failure (5.3 per cent). The rate of death from cancer is 8.9 per cent and the five-year survival rate is 76 per cent. In patients under 60 years, a perirectal lymphadenectomy should be considered a safety measure. A new approach, based on a combination of external beam irradiation (3000 rads in 12 days), followed by iridium 192 implant two months later, allows the field of conservative treatment in poor-risk surgical patients to be extended without jeopardizing their chance of cure.