Anorectal Carcinoid Tumors

Abstract

The management of large carcinoid tumors of the anorectum is controversial. Most carcinoid tumors of the rectum and anus are early lesions, adequately treated by local excision. However, because of their relative rarity, the number of advanced cases seen at most institutions is small. Forty-three patients with anorectal carcinoid tumors were treated at our institution between 1960 and 1988 with complete follow-up. The median age of onset was 56 years. Eleven patients had no symptoms and the tumor was detected incidentally in eight additional patients with other diseases. Twenty tumors were larger than 2 cm in diameter and all patients had symptoms. Eight patients had another malignancy and three patients had ulcerative colitis. An association between ulcerative colitis and rectal carcinoid tumors is not widely appreciated. Eighteen tumors were treated by local excision, 16 by radical surgery, and nine underwent only biopsy. With complete resection of the primary lesion, local recurrence was never a problem. The median survival from diagnosis was 38 months in this series and 23 patients died of disease. After detection of metastases, the median survival time was 10 months. Tumors more advanced that T2 or larger than 2 cm in diameter were always fatal. All 13 patients with involved lymph nodes died of metastatic disease, with a median survival of 10 months, although one lived 9 years. Advanced rectal carcinoid tumors are aggressive malignancies. Adequate local excision controls regional disease but rectal carcinoid tumors are cured only when they are discovered before the T3 stage, measure less than 2 cm in diameter, and when lymph nodes are not involved. Consequently if a local excision permits complete resection, radical extirpative surgery will provide little benefit.