Are Width, Length, Depth and Area of Submucosal Invasion Predictive for Lymph Nodes Metastasis in pT1 Colorectal Cancer?

Abstract

Abstract Background and study aim: Colorectal carcinomas limited by submucosa (pT1) remain the challenge in terms of choice for treatment options from local excision to radical surgery. The aim of the study was to evaluate morphometric and morphologic risk factors of regional lymph nodes metastasis (LNM) for pT1 colorectal carcinoma (CRC). Patients and methods: The histology of patients undergoing oncological resection from 2016 to 2022 was reviewed. Tumor grade (G), budding (Bd), poorly differentiated clusters (PDC), cancer gland rupture (CGR), lymphovascular invasion (LVI) and deep submucosal invasion (DSI) as well as width, length, total area and deep submucosal invasion (DSI) were evaluated as risk factors of LNM. Results: Two hundred and sixty-four cases of colon and rectal carcinomas with invasion into the submucosal layer (pT1) were identified. Of them LNM was found in 46/264 (17.4%) cases. All morphometric parameters and DSI (p=0.33) failed to demonstrate association with LNM. High grade (G3) (p=0.05), Bd (p=0.056) and PDC (p<0.0001) were associated with LNM. In multivariate analysis LVI+ remains the only significant independent risk factor [OR 15.7; 95% CI 8.5 - 94.9] (p<0.0001). Conclusion: The DSI invasion of T1 CRC as well as other morphometric parameters of submucosal tumor spread do not have any predictive value in terms of LNM. Poor differentiation of colorectal carcinoma, tumor budding (Bd), poorly differentiated clusters (PDC) and lymphovascular invasion (LVI) are the significant risk factors for LNM in T1 CRC. Among them LVI was the only independent risk factor.