Unusual presentations of carcinoma of the right colon.

Two unusual presentations of carcinoma of the right colon are described. One of the two patients presented with a right gluteal abscess and the other presented with a colocutaneous fistula to the anterior abdominal wall at the site of a previous appendectomy scar. Despite extensive local tumor invasion of adjacent structures in both cases, all the regional lymph nodes were free of cancer and the tumors were of low-grade malignancy. A review of the literature indicates that bulky colonic tumors with extensive local invasion and negative mesenteric lymph nodes have a relatively good prognosis if adequate resection is performed.