Primary lymphoma of the large intestine.

Three cases of primary colonic lymphoma are presented and the literature for this disease is reviewed. Colonic lymphoma occurs in from 0.5 to 2 per cent of all cases of neoplastic disease of the colon, and comprises 15 to 20 per cent of cases of primary gastrointestinal lymphoma. The disease can occur at any age, from 3 years to 89 years; the average age is 50 years. Men are affected twice as often as women. The disease most commonly presents as a painful abdominal mass. The cecum is the area of involvement in 70 per cent of cases. The tumors are usually large, averaging over 7 centimeters. The most common histological types are histiocytic or lymphocytic tumors. Surgery is the principle treatment mode; about half are thought to be potentially curable at the time of surgical exploration. The role of adjuvant therapy has not yet been clearly defined, although data from some studies indicate increased survival in those patients given adjuvant radiation therapy. Survival is decreased in patients with tumors larger than 5 centimeters or with histiocytic cell type. Overall 5-year survival is 39 per cent.