Colon cancer: diagnosis and prognosis in the elderly.

Cancer of the colon and rectum appear to be epidemic in the US, with 150,000 cases expected during 1988. Two thirds of these patients are over age 60, and two thirds also have either full penetration of the bowel wall or metastases to regional lymph nodes. Mass screening via tests for occult blood in the stool is invaluable for detecting early carcinomas of the colon and rectum. Digital examination, endoscopy, and barium contrast radiographs help to confirm the diagnosis. Tumors of the colon and rectum are best treated operatively with appropriate lymphadenectomy and adequate margins, both proximally and distally, to guard against local recurrence. Certain factors, such as mucinous tumors, microinvasion, and non-exophytic tumors of the rectum have been shown to have a propensity for local recurrence. Local treatment by fulguration or electrocoagulation is advocated only for tiny tumors confined to a polyp, or for the extremely elderly or poor-risk patient. Radiation therapy appears to be an appropriate adjuvant to the treatment of rectal cancer either preoperatively or postoperatively.