Usefulness of analyzing endoscopic features in identifying the colorectal serrated sessile lesions with and without dysplasia

BACKGROUND: Sessile serrated lesions (SSLs) are often missed on colonoscopy, and studies have shown this to be an essential cause of interstitial colorectal cancer. The SSLs with dysplasia (SSL-D(+)), in particular, have a faster rate of carcinogenesis than conventional tubular adenomas. Therefore, there is a clinical need for some endoscopic features with independent diagnostic value for SSL-D(+)s to assist endoscopists in making immediate diagnoses, thus improving the quality of endoscopic examination and treatment. AIM: To compare the characteristics of SSLs, including those with and without dysplasia (SSL-D(+) and SSL-D(-)), based on white light and image-enhanced endoscopy, to achieve an immediate differential diagnosis for endoscopists. METHODS: From January 2017 to February 2023, cases of colorectal SSLs confirmed by colonoscopy and histopathology at the Gastrointestinal Endoscopy Center of Beijing Tsinghua Changgung Hospital were collected. The general, endoscopic, and histopathological data were reviewed and analyzed to determine the diagnostic utility. Univariate analysis was used to find potential diagnostic factors, and then multivariate regression analysis was performed to derive endoscopic features with independent diagnostic values for the SSL-D(+). RESULTS: A total of 228 patients with 253 lesions were collected as a result. There were 225 cases of colorectal SSL-D(-)s and 28 cases of SSL-D(+)s. Compared to the colorectal SSL-D(-), the SSL-D(+) was more common in the right colon (P = 0.027) with complex patterns of depression, nodule, and elevation based on cloud-like surfaces (P = 0.003), reddish (P < 0.001), microvascular varicose (P < 0.001), and mixed type (Pit II, II-O, IIIL, IV) of crypt opening based on Pit II-O (P < 0.001). Multifactorial logistic regression analysis indicated that lesions had a reddish color [odds ratio (OR) = 18.705, 95% confidence interval (CI): 3.684-94.974], microvascular varicose (OR = 6.768, 95%CI: 1.717-26.677), and mixed pattern of crypt opening (OR = 20.704, 95%CI: 2.955-145.086) as the independent predictors for SSL-D(+)s. CONCLUSION: The endoscopic feature that has independent diagnostic value for SSL-D(+) is a reddish color, microvascular varicose, and mixed pattern of crypt openings.