USE OF ENDOSONOGRAPHIC EVALUATION OF COLORECTAL TUMOR DEPTH IN DETERMINING THE APPROPRIATENESS OF ENDOSCOPIC MUCOSAL RESECTION

Objectives: To determine the efficacy with which endoscopic ultrasonog raphy (EUS) is able to differentiate between mucosal and submucosal in vasion for application of endoscopic resection. Methods: We prospectiv ely analyzed 60 patients who were diagnosed with early cancer by conve ntional EUS with regard to the accuracy of mucosal neoplasia as a func tion of gender, age, location, size, endoscopic configuration, histolo gical diagnosis, and method of resection. Results: Forty lesions inter preted as mucosal by EUS were shown histologically to include 32 lesio ns in the mucosa and eight in the submucosa or deeper, whereas 20 tumo rs interpreted as invasive cancer included six lesions in the mucosa a nd 14 in the submucosa or deeper. The accuracy of mucosal neoplasia (A MN) detection was 77% (true-positive and true-negative mucosal neoplas ias divided by ail lesions). Assessment of pure cancers without adenom atous components produced a significantly lower AMN (59%, p = 0.03) th an the assessment of pure adenomas (95%) or cancers in adenomas (87%). However, there were no significant differences in the EUS assessment of intramucosal neoplasia as a function of sex, age, endoscopic config uration, size, location, or treatment. Conclusions: We conclude that c onventional EUS interpretation alone cannot determine the appropriate treatment for early colorectal cancer.