Prognostic Impact of Extramural Lymphatic, Vascular, and Perineural Invasion in Stage II Colon Cancer: A Comparison With Intramural Invasion

BACKGROUND: Lymphatic invasion, vascular invasion, and perineural invasion are prognostic factors for colon cancer. However, the prognostic significance of those factors according to the location of permeation (intramural and extramural invasion) in stage II colon cancer is still unclear.OBJECTIVE: This study aimed to clarify whether the location of lymphatic invasion, vascular invasion, and perineural invasion could affect the survival of patients with stage II colon cancer.DESIGN: This was a retrospective cohort study.SETTINGS: This study took place at a university teaching hospital.PATIENTS: A total of 1130 patients with stage II colon cancers who underwent radical surgery at the Seoul National University Hospital between July 2003 and December 2015 were included.MAIN OUTCOME MEASURES: Patients were classified according to the location of lymphatic invasion, vascular invasion, and perineural invasion. Survival outcomes were compared among those without invasion and those with intramural and extramural invasion. Primary end point is overall survival and secondary end point is disease-free survival.RESULTS: Disease-free survival and overall survival of patients with extramural invasion were worse than those of patients without invasion and those with intramural invasion. Multivariate analysis for survival outcomes confirmed that extramural invasion was a significant independent prognostic factor. However, both disease-free survival and overall survival were not significantly different between patients without invasion and those with intramural invasion.LIMITATIONS: This study was limited by its retrospective design.CONCLUSIONS: Extramural invasion was associated with worse prognosis in stage II colon cancer, but intramural invasion was not. Therefore, pathologic reports about the location of lymphatic invasion, vascular invasion, and perineural invasion might be helpful for predicting prognosis and for determining the need of adjuvant chemotherapy in stage II colon cancers.