PURPOSE: There is increasing interest in immune function in combination with chemotherapy for cancer treatment. However, the effects of chemotherapy on the human immune system remain to be determined. The aim of this study was to investigate the prognostic impact of lymphocyte and neutrophil counts in colon cancer patients who were treated with curative surgery and adjuvant chemotherapy.
METHODS: Two hundred thirty-one patients with colon cancers who underwent curative surgery and FOLFOX adjuvant chemotherapy between November 2005 and December 2011 were included. Oncologic outcomes were analyzed with neutrophil count, lymphocyte count, and neutrophil-to-lymphocyte ratio (NLR) before and after chemotherapy.
RESULTS: The 5-year DFS rate was lower in colon cancer patients with low lymphocyte count during chemotherapy (61.9 vs. 76.7%, P = 0.026). Cox multivariate analysis demonstrated that low lymphocyte count during chemotherapy was independently associated with poor disease-free survival (HR 1.829: 95% CI 1.096-3.050: P = 0.021) in colon cancer patients who underwent FOLFOX adjuvant chemotherapy.
CONCLUSION: Lymphocyte count during chemotherapy is a strong predictor of worse disease-free survival in colon cancer patients who have undergone FOLFOX adjuvant chemotherapy.