Comparison of vascular invasion with lymph node metastasis as a prognostic factor in stage I-III colon cancer: an observational cohort study

Abstract

<jats:title>Abstract</jats:title> <jats:p><jats:bold>Background:</jats:bold> The oncological impact of vascular invasion (VI), when compared with that of lymph node metastasis (LNM), has been underestimated in clinicopathological staging of colon cancer. This study aimed to evaluate the prognostic impact of VI in comparison with that of LNM in non-metastatic colon cancer.<jats:bold>Methods:</jats:bold> Patients who underwent surgery for stage I-III colon cancer were divided into four groups depending on the status of VI and LNM (Group I: VI-/LNM-; Group II: VI+/LNM-; Group III: VI-/LNM+; Group IV: VI+/LNM+). Group III was subdivided according to the node (N) stage (Group IIIA: VI-/N1; Group IIIB: VI-/N2). Disease-free survival (DFS) and overall survival were compared.<jats:bold>Results:</jats:bold> In total, 793 non-metastatic colon cancer patients were included. Group II (hazard ratio [HR] 2.34, 1.01-5.41), Group III (HR 1.91, 1.26-2.89), and Group IV (HR 2.34, 1.33-4.14) were independently associated with poor DFS. All recurrences in Group II occurred within 2 years and were distant metastases. The 1- and 2-year DFS rates were 76.3% and 71.6% in Group II and 88.3% and 79.8% in Group III, respectively (<jats:italic>P </jats:italic>= 0.067 and 0.247). In subgroup analysis, the 5-year DFS rates tended to be lower in Group II (71.6%) than in Group IIIA (79.7%) and higher than those in Group IIIB (61.4%).<jats:bold>Conclusion:</jats:bold> VI is a prognostic factor as significant as LNM and may be regarded as a stronger prognostic factor than N1 stage in non-metastatic colon cancer. Furthermore, a potential association was observed between VI and recurrence patterns, such as early recurrence and distant metastasis.</jats:p>