Preoperative peripheral blood neutrophil count predicts long-term outcomes following hepatic resection for colorectal liver metastases.

Preoperative systemic inflammatory response is associated with a poor long-term prognosis following resection surgery for malignant tumors. Several markers of systemic inflammation have been reported to be associated with the outcome; however, they have not currently been fully investigated. Therefore, the association between preoperative peripheral blood neutrophil count and oncological outcome following hepatic resection for colorectal liver metastasis (CRLM) was retrospectively investigated. The present study comprised 89 patients who had undergone hepatic resection for CRLM between January 2000 and March 2010. The association between preoperative peripheral blood neutrophil count and disease-free survival, in addition to overall survival, was investigated. In multivariate analysis, the presence of neoadjuvant chemotherapy (P=0.015), bilobar distribution (P=0.015) and neutrophil count ≥3,500/µl (P=0.025) were independent and significant predictors of poor disease-free survival, while significant predictors of poor overall survival consisted of >4 lymph node metastases (P=0.001), neo-adjuvant chemotherapy (P=0.003), bilobar distribution (P=0.039) and neutrophil count ≥3,500/µl (P=0.040). Additionally, tumor diameter (P=0.021) and monocyte count (P<0.0001) were observed to be significantly greater in the elevated neutrophil count group. In conclusion, preoperative peripheral blood neutrophil count may be an independent and significant indicator of poor long-term outcomes in patients with CRLM following hepatic resection.