Endoscopic ultrasonography in the diagnosis of submucosal lesions of the large intestine

Background: Although reports of colorectal submucosal tumors have increased since the development of endoscopic examinations, precise diagnosis of these lesions remains difficult. In this study, we evaluated the usefulness of endoscopic ultrasonography (EUS) in the diagnosis of submucosal lesions of the large intestine. Methods: From September 1989 to June 1996, EUS was performed in 46 patients who were suspected to have submucosal lesions by barium enema or colonoscopy, Twenty-seven of the 46 Gases were confirmed histologically by endoscopic or surgical resection, and their ultrasonographic images were compared with resection specimens. Results: Lipomas (n = 15) were visualized as hyperechoic masses and lymphangiomas (n = 9) visualized as cystic lesions with septal structures as characteristic findings. The EUS images of leiomyomas (n = 6), leiomyosarcomas (n = 3), and enteric endometriosis (n = 7) were all hypoechoic masses in the fourth layer. Leiomyosarcomas tended to be larger and more inhomogeneous than leiomyomas, Enteric endometriosis was shaped like a spindle or a half-moon, and myogenic tumors were lobulated when the lesions were large. Recurrences of colorectal carcinoma (n = 3), malignant lymphomas (n = 2), and an appendiceal mucocele (n = 1) were examined. Conclusions: EUS is useful in the diagnosis of submucosal lesions of the large intestine because it provides precise information about these lesions.