Objectives: The prognostic value of several hematologic parameters, including platelet, lymphocyte, and neutrophil counts, has been studied in a variety of solid tumors. In this study, we examined the significance of inflammatory markers and their prognostic implications in patients with colorectal cancer (CRC).
Materials and methods: Patients with stage I-III CRC who underwent surgical resection at the Stanford Cancer Institute between 2005 and 2009 were included. Patients were excluded if they did not have preoperative complete blood counts performed within 1 month of surgical resection, underwent preoperative chemotherapy or radiation, had metastatic disease at diagnosis, or had another previous malignancy. We included 129 eligible patients with available preoperative complete blood counts in the final analysis.
Results: A preoperative neutrophil-to-lymphocyte ratio of>3.3 was significantly associated with worse disease-free (DFS) and overall survival (OS) (P=0.009, 0.003), as was a preoperative lymphocyte-to-monocyte ratio of ≤2.6 (P=0.01, 0.002). Preoperative lymphopenia (P=0.002) was associated with worse OS but not DFS (P=0.09). In addition, preoperative thrombocytosis was associated with worse DFS (P=0.006) and OS (P=0.010). Preoperative leukocytosis was associated with worse OS (P=0.048) but not DFS (P=0.49). Preoperative hemoglobin was neither associated with OS (P=0.24) or DFS (P=0.15).
Conclusions: Pretreatment lymphopenia, thrombocytosis, a decreased lymphocyte-to-monocyte ratio, and an elevated neutrophil-to-lymphocyte ratio independently predict for worse OS in patients with CRC.