Endoscopic features for differentiating sessile serrated lesion with dysplasia or carcinoma in serrated lesions ≥10 mm.

Background and aim: Accurate differentiation of sessile serrated lesion with dysplasia (SSLD) or with carcinoma (SSL+Ca) from hyperplastic polyp (HP) and sessile serrated lesion (SSL) is crucial for appropriate endoscopic management.

Methods: This single-center retrospective study included colorectal serrated lesions (≥10 mm) resected between 2017 and 2020 and pathologically diagnosed as HP, SSL, SSLD, or SSL+Ca based on the WHO 5th edition criteria. Characteristic factors associated with SSLD/SSL+Ca and their diagnostic performance were analyzed. Additionally, features of submucosal invasive (pT1) SSL+Ca were examined.

Results: Among 498 lesions, 23 (4.6 %) were diagnosed as SSLD/SSL+Ca, with prevalence increasing by size (10-14 mm: 1.2 %, 15-19 mm: 9.2 %, ≥20 mm: 14.3 %). Multivariate analysis identified lesion size ≥15 mm, double elevation, and neoplastic JNET type (2A/2B/3) as significant predictors. A prediction model using these factors demonstrated high diagnostic accuracy (sensitivity 91.3 %, specificity 91.8 %, accuracy 91.8 %, PPV 35.0 %, NPV 99.5 %). In pT1 SSL+Ca, JNET Type 3, Kudo's type V pit pattern, and non-lifting sign were significantly associated.

Conclusions: Among HP and SSL ≥10 mm, the prevalence of SSLD/SSL+Ca increased with lesion size. Double elevation and neoplastic JNET type were valuable for diagnosis, aiding appropriate management.