Late development of colorectal cancer subsequent to pelvic irradiation.

Two cases of irradiation-associated carcinoma of the colon are reported and the literature reviewed. The clinical courses and operative difficulties in treating these patients are emphasized. The necessity for life-long follow-up examinations with proctoscopic and barium-enema evaluations in high-risk patients is stressed. Irradiation-associated carcinoma of the colon occurs almost exclusively in women, but should be investigated in patients of either sex who live for long periods after pelvic irradiation.