CARCINOID TUMORS OF THE RECTUM

Over the last 18 years, 13 patients with carcinoid tumors of the rectum have been treated at the hospital. Their incidence was at 3.5 percent of rectal cancers. Most patients complained of non-specific anorectal symptoms such as diarrhea or anal bleeding, and some patients were asymptomatic. The lesions occurred frequently in the middle or lower third of the rectum within 10 cm from the anal verge and were usually found as submucosal nodules or polypoid lesions. Eleven lesions were less than 20 mm in diameter and localized in the submucosal layer. Two lesions were 20 mm or larger in diameter with invasion of the muscularis propria. Twelve patients received local excisions and only one patient with invasive disease took radical operation. There was no evidence of lymph nodes involvement in all 13 cases. Among the patients with the lesions smaller than 20 mm, none had local recurrence or distant metastasis. In contrast, two patients with the lesions 20 mm or larger died of hepatic metastasis. These findings suggest that both tumor size and the depth of invasion have prognostic importance for carcinoid tumors of the rectum. Thus, local excisions can be elected in lesions smaller than 20 mm in diameter, but when the tumor is 20 mm or larger the patient should have a cancer type radical operation.