Effects of serum total lymphocyte number on clinicopathological features and overall survival outcome for cases with rectal cancer who received radical resection

Objective We aimed to evaluate the clinical significance and long-term survival outcome of total lymphocyte number, one of the preoperative nutritional status markers, for cases with rectal cancer who received radical resection. Methods 528 cases with rectal cancer who received radical surgery were divided into two groups according to the total lymphocyte number, there are low level lymphocyte number group (total lymphocyte number<1.7×109/L) and normal level lymphocyte number group (total lymphocyte number≥1.7×109/L). The differences of clinicopathological features and survival outcome were compared between two groups. Results There were more senile patients and larger proportion of infiltrative type in the low level lymphocyte number group. We found the cases in the low level lymphocyte number group were more likely to be associated with advanced tumor depth stage, lymph node involvement, distant metastasis, TNM classification, Dukes stage. The 5 year overall survival rates of patients in the low level lymphocyte number group and normal level lymphocyte number group was 30.3% and 52.8% respectively and the survival difference had statistical significance. The low level lymphocyte number was deemed as a poor independent prognosis by the univariate and multivariate regression analysis. Conclusions The low level lymphocyte number, one of the serum markers for malnutrition, were correlated with worse clinicopathological features and long-term prognosis. The effect of nutrition support for cases with rectal cancer who received radical resection still need further large-scale clinical verification. Key words: Rectal neoplasms; Surgical procedures, operative; Total lymphocyte number; Prognosis