Histological Inflammatory Cell Infiltration Is Associated with the Number of Lymph Nodes Retrieved in Colorectal Cancer

Abstract

Background: Antitumor immune response is suggested to be a factor affecting the number of nodes retrieved after colorectal cancer surgery. The purpose of this study was to evaluate the correlation of antitumor immune response with the number of retrieved nodes. Patients and Methods: Patients with colorectal cancer (n=63, TNM stage II and III) were enrolled. Inflammatory cell infiltration (ICI) was assessed on hematoxylin and eosin staining and T-cell markers (CD3, CD8, CD45RO) were evaluated using immunohistochemical methods. Results: On univariate analysis, high ICI, CD3 and CD8 expression were associated with a greater number of nodes being retrieved. On multivariate analysis, tumors of the right colon (p=0.01) and high ICI (p=0.04) were independent predictors of a greater retrieval of nodes. TNM stage III tumor with low ICI was associated with reduced cancer-specific survival (p=0.02). Conclusion: ICI influences the number of nodes retrieved and affects survival of patients with stage III disease. Antitumor immune response may be an underlying factor determining the number of nodes retrieved after surgery for colorectal cancer.