Histopathological risk factors for lymph node metastasis in submucosal invasive colorectal carcinoma of pedunculated or semipedunculated type

Aims: To evaluate the histopathological risk factors for lymph node metastasis in cases of pedunculated or semipedunculated submucosal invasive colorectal carcinoma (SICC). Methods: A total of 48 patients with non-sessile SICC who underwent systematic lymph node dissection were included. Tumour size, histological grade, angiolymphatic invasion, tumour budding, dedifferentiation, objective submucosal invasion depth from the identified muscularis mucosa, relative invasion depth of the submucosal layer, and depth of stalk invasion were investigated histopathologically. Results: Lymph node metastasis was observed in seven cases (14.6%). Univariate analysis showed angiolymphatic invasion and tumour budding to be significantly associated with lymph node metastasis. Multivariate analysis showed that tumour budding was the only independent factor associated with lymph node metastasis in cases of non-sessile SICC. Conclusions: Results indicate that tumour budding is a useful risk factor for predicting lymph node metastasis in cases of pedunculated or semipedunculated SICC.