The relationship between involved lymph nodes, metastatic nest diameters and prognosis in colorectal cancer.

INTRODUCTION Several studies evaluated the relation between colorectal cancer prognosis and various factors such as: depth of tumor invasion, involved lymph nodes size, counts and locations, metastatic nest expansion. We assessed the prognostic significance of the ratio between metastatic nest and involved lymph node diameter in colorectal cancer cases. METHODS A historical cohort study was conducted on patients with known colorectal cancer and metastatic lymph nodes (Astler Coller's stage C), in whom diagnosis was confirmed at least one year before the study. Less than two months following surgery, patients were treated with the same chemotherapy protocol. Metastatic lymph node sizes were recorded in 63 pathologic samples. Metastatic nest borders were marked using a marker and a 40x magnifying microscope. The greatest metastatic nest to involved lymph node diameter ratio was obtained. The data were analyzed with SPSS analytic software. Actuarial and Kaplan-Meier methods were used to estimate survival. Survival functions were compared by Log rank and Cox regression tests. RESULTS There was no significant relation between colorectal cancer prognosis and: the greatest involved lymph node diameter, the metastatic nest diameter and the ratio metastatic nest to involved lymph node diameter (p-values in sequence: 0.1, 0.07, 0.2). CONCLUSION We found no significant relationship between the colorectal cancer prognosis and the greatest lymph node diameter, the greatest metastatic nest diameter and the greatest metastatic nest to involved lymph node diameter ratio. Further studies are required in order to reach a decisive conclusion.