Cancers of the colon (large intestine) and rectum together make up the second leading cause of cancer death in the United States, claiming an estimated 45,000 lives annually. Scientists believe that many of these deaths could be prevented by early detection and treatment. Accordingly, a routine examination of the colon and rectum in a physician's office with a lighted tube called a proctosigmoido-scope is recommended in health checkups of all persons over 40.
The most effective treatment is surgery. The operation usually consists of removing the part of the bowel containing the tumor, adjacent segments of bowel, and regional lymph nodes. If cancer is widespread, extensive surgery may be required and the surgeon may create a colostomy, a permanent or temporary opening in the abdominal wall to permit elimination of solid wastes. Bowel function is usually unimpaired and, after adjusting to some inconvenience, the patient with a colostomy may lead an otherwise normal, active life.
Radiotherapy may be a useful adjunct to surgery, administered before operation or for recurrence of disease following surgery. For some patients radiotherapy makes surgery possible.
Cancer of the colon and rectum constitute the seconds leading cause of cancer deaths in the United States. However, survival rates increase with early detection and surgical treatment.
In metastatic cancers of the colon and rectum, 5-FU and thioTEPA sometimes temporarily control the disease. In reports made over the years as many as 41 percent and as few as 8 percent of patients treated with 5-FU have responded favorably.
In 1968 scientists reported that 5-FU injected inside the bowel during a surgical procedure that employs a bowel-isolation technique, followed by 5-FU given intravenously on the first and second postoperative days, was of benefit to patients whose disease had spread to regional lymph nodes. Thirteen of 21 patients (65 percent) treated by this technique were alive 5 years or longer, as contrasted with 32 percent of patients with similarly advanced disease reported in a nationwide survey of survival. Used in the same manner, nitrogen mustard was not as effective as 5-FU.
In another study comparing drug effectiveness in colon cancer, 5-FU was the most effective drug and phenylalanine mustard the next most active. Vinblastine sulfate and cyclophosphamide had activity against lymphomas localized in the gastrointestinal tract.
In a small group of cases of colon cancer in another study, about a third of the patients responded to Mitomycin C.
Combination chemotherapy appears worthy of further clinical investigation. In a midwest-ern study of various single drugs and drug combinations, the highest remission rate among 74 patients with advanced cancer of the colon was achieved in a small group who received combination chemotherapy with methotrexate and TEM, followed by nitrogen mustard, 5-FU, and/or thioTEPA.