Studies on Determination of Surgical Proceduces for Carcinoid Tumor of the Rectum According to Findings of Invasing Depth and Regional Lymphnode Metastasis Using Endscophic Ultrasonography

From 1989 to 1992, we experienced eight cases of rectal carcinoid. The depth of invasion in 6 cases was examined by preoperative EUS and histological examination of the resected specimen was performed in all of the cases. The tumor size was less than 1cm except for a case with a tumor measuring 2cm in diameter. EUS before operation revealed submucosal invasion in four cases and invasion in the upper part of the proper muscle layer in one case. Assessment of invasion with EUS was not possible in the case who received clip marking at biopsy. In 5 cases, the results of histology was confined to invasion and the correct assessment of the invasion with EUS. Lymphnode metastasis around the rectum was not found by neither EUS nor histology of the surgical specimens in to the 6 cases. Among two cases without preoperative EUS, one case in whom assessment of invasion with EUS was not possible and another case with suspicious invasion to the proper muscle layer received local resection of the tumor. A case with submucosal invasion and multiple liver metastasis also received local resection by sacroperineal approach. Three cases diagnosed as having submucosal invasion by EUS underwent endoscopic mucosal resection. We concluded that treatment procedures for rectal carcinoid was possible to determine before surgery by preoperative findings of EUS.