Effectiveness of local endoscopic resection of rectal carcinoid tumors

In the treatment of rectal carcinoid tumors, confusion arises in the choice between radical surgery and local endoscopic resection, since the malignancy of individual tumors differs widely. We investigated the appropriateness of using endoscopic therapy for this disease.

Twenty-two patients were diagnosed with rectal carcinoid tumors at the First Department of Internal Medicine, Yamaguchi University School of Medicine and its affiliated hospitals, from 1977 to 1994. The tumors were resected and examined regarding their size, depth of invasion, and histological atypia. The post-treatment course in patients whose tumors were completely resected without atypia was observed by colonoscopy and ultrasonography at yearly intervals.

In 21 patients, tumor invasion did not extend beyond the submucosal layer, and there were no signs of atypia. The size of the tumor varied from 2.2 mm to 10.0 mm in diameter, with an average of 5.4 mm. After endoscopic resection of the tumors in 18 patients and surgical local resection in three patients, no local recurrences or liver metastases were experienced. The patients survived for a minimum of 29 months and a maximum of 237 months; the mean survival period was 72.8 months. In one patient, the tumor showed cellular atypia invading into the tunica muscularis, and measured 25 mm in diameter. The patient underwent surgery, but died ten months later due to liver metastasis.

Endoscopic treatment of rectal carcinoid tumors was found to be appropriate when the tumor measured 10 mm or less in diameter, did not infiltrate beyond the submucosal layer, and had no histological atypia.