GASTROINTESTINAL SUBMUCOSAL TUMORS - EVALUATION WITH ENDOSCOPIC US

PURPOSE: To describe the endoscopic ultrasound (US) features of benign versus malignant submucosal tumors throughout the gastrointestinal tr act. MATERIALS AND METHODS: One hundred nine patients aged 24-81 years suspected to have submucosal tumors (11 esophageal, 41 stomach, 24 du odenal, and 33 colorectal tumors) at barium studies or endoscopy under went endoscopic US. The layer of origin, internal echo pattern, and le sion margin were analyzed by means of consensus and independent interp retation by three radiologists. RESULTS: Endoscopic US findings reveal ed several distinct patterns among various submucosal tumors. Sixteen (94%) of the 17 homogeneous lesions with histopathologic findings of m alignancy were hypoechoic, although 29 (43%) of the 68 homogeneous les ions with histopathologic findings of benignity were similarly hypoech oic. Homogeneous lesions that were anechoic, of intermediate echogenic ity, or hyperechoic were almost exclusively benign (39 [98%] of 40). I n contrast 23 (96%) of the 24 malignant lesions were heterogeneous (n = 7) or homogeneously hypoechoic (n = 16). The sizes of benign and mal ignant lesions were significantly different (P < .05). There was no si gnificant difference in the echo pattern (ie, homogeneous versus heter ogeneous), but there was a significant difference in the proportion of hypoechoic versus nonhypoechoic lesions (anechoic, hyperechoic, or of intermediate echogenicity; P < .001). CONCLUSION: The differential di agnosis of gastrointestinal submucosal tumors is assisted with endosco pic US.