Objective:To identify the factors influencing the diagnostic accuracy of endoscopic ultrasonography (EUS) for colorectal submucosal tumors (SMT).Methods:A retrospective analysis was conducted on 330 colorectal SMT lesions (from 323 patients) diagnosed by EUS at Shenzhen Hospital of Southern Medical University from December 2015 to October 2023. Pathological diagnosis were confirmed through endoscopic resection, EUS-guided fine needle aspiration (EUS-FNA) or surgical resection. Diagnostic accuracy was calculated for each type of colorectal SMT. Univariate and multivariate logistic regression analysis were performed to identify factors affecting EUS diagnostic accuracy.Results:The overall diagnostic accuracy of EUS for colorectal SMT was 73.6% (243/330). Among 19 SMT subtypes enrolled, neuroendocrine neoplasms (51.2%, 169/330) and lipomas (15.5%, 51/330) were most prevalent, while 17 rare subtypes each accounted for <6%. Seven rare SMT (mucosal chronic inflammation, colorectal schwannoma, xanthogranulomatous inflammation, capillary hemangioma, colonic xanthoma, lymphadenoid complex, and angiomyolipoma) showed 0% diagnostic accuracy. Seven other subtypes (granular cell tumor, leiomyoma, rectal tonsil, intestinal schistosomiasis, fibrous tissue hyperplasia, gastrointestinal stromal tumor, and lymphangioma) showed accuracy <30%, whereas five subtypes (cyst, bowel endometriosis, neuroendocrine neoplasm, lipoma, and pneumatosis cystoides intestinalis) achieved >60% accuracy. Multivariate logistic regression analysis confirmed that the lesion location (left colon VS rectum: OR=0.06, 95% CI: 0.02-0.17, P<0.001; right colon VS rectum: OR=0.04, 95% CI: 0.01-0.13, P<0.001; ileocecal valve VS rectum: OR=0.09, 95% CI: 0.02-0.42, P=0.002); echogenicity (anechoic VS hypoechoic: OR=6.26, 95% CI: 1.31-29.97, P=0.022; hyperechoic VS hypoechoic: OR=13.39, 95% CI: 4.16-43.09, P<0.001) and ultrasonic layer (layer 4 VS layer 3: OR=0.22, 95% CI: 0.06-0.81, P=0.023) were independent influencing factors of EUS diagnostic accuracy for colorectal SMT. Conclusion:Neuroendocrine neoplasms and lipomas represent the most common colorectal SMT, whereas rare and uncommon SMT exhibit low EUS diagnostic accuracy. Lesion location, echogenicity, and ultrasonic layer significantly influence EUS diagnostic accuracy for colorectal SMT.

Objective:To identify the factors influencing the diagnostic accuracy of endoscopic ultrasonography (EUS) for colorectal submucosal tumors (SMT).Methods:A retrospective analysis was conducted on 330 colorectal SMT lesions (from 323 patients) diagnosed by EUS at Shenzhen Hospital of Southern Medical University from December 2015 to October 2023. Pathological diagnosis were confirmed through endoscopic resection, EUS-guided fine needle aspiration (EUS-FNA) or surgical resection. Diagnostic accuracy was calculated for each type of colorectal SMT. Univariate and multivariate logistic regression analysis were performed to identify factors affecting EUS diagnostic accuracy.Results:The overall diagnostic accuracy of EUS for colorectal SMT was 73.6% (243/330). Among 19 SMT subtypes enrolled, neuroendocrine neoplasms (51.2%, 169/330) and lipomas (15.5%, 51/330) were most prevalent, while 17 rare subtypes each accounted for <6%. Seven rare SMT (mucosal chronic inflammation, colorectal schwannoma, xanthogranulomatous inflammation, capillary hemangioma, colonic xanthoma, lymphadenoid complex, and angiomyolipoma) showed 0% diagnostic accuracy. Seven other subtypes (granular cell tumor, leiomyoma, rectal tonsil, intestinal schistosomiasis, fibrous tissue hyperplasia, gastrointestinal stromal tumor, and lymphangioma) showed accuracy <30%, whereas five subtypes (cyst, bowel endometriosis, neuroendocrine neoplasm, lipoma, and pneumatosis cystoides intestinalis) achieved >60% accuracy. Multivariate logistic regression analysis confirmed that the lesion location (left colon VS rectum: OR=0.06, 95% CI: 0.02-0.17, P<0.001; right colon VS rectum: OR=0.04, 95% CI: 0.01-0.13, P<0.001; ileocecal valve VS rectum: OR=0.09, 95% CI: 0.02-0.42, P=0.002); echogenicity (anechoic VS hypoechoic: OR=6.26, 95% CI: 1.31-29.97, P=0.022; hyperechoic VS hypoechoic: OR=13.39, 95% CI: 4.16-43.09, P<0.001) and ultrasonic layer (layer 4 VS layer 3: OR=0.22, 95% CI: 0.06-0.81, P=0.023) were independent influencing factors of EUS diagnostic accuracy for colorectal SMT. Conclusion:Neuroendocrine neoplasms and lipomas represent the most common colorectal SMT, whereas rare and uncommon SMT exhibit low EUS diagnostic accuracy. Lesion location, echogenicity, and ultrasonic layer significantly influence EUS diagnostic accuracy for colorectal SMT.