Prognostic value of red cell distribution width combined with lactate dehydrogenase in patients with colorectal liver metastases

Objective To investigate the prognostic value of red cell distribution width (RDW) plus lactate dehydrogenase (LDH) in patients with colorectal liver metastases (CLM). Methods Clinical data about 34 patients diagnosed with synchronous colorectal cancer liver metastases and underwent simultaneous radical resection surgery in the First Medical Center of Chinese PLA General Hospital from January 2016 to October 2017 were retrospectively analyzed.RDW,LDH within a week before surgery,relevant clinical data and pathology results were collected.Patients with CLM were followed up for two years.Patients were divided into survival group and death group according to their survival outcomes within two years.Cox proportional hazards model was used to analyze the independent influencing factors.CLM patients were further divided into low-risk group (n=26) and high-risk group (n=8) according to the thresholds calculated by ROC curves.Kaplan-Meier curves were drawn to compare the overall survival (OS) between the high-risk group and the low-risk group within two years after surgery. Results The RDW (16.22±5.10 vs 12.93±1.04,P=0.036) and LDH (16.22±5.10 vs 12.93±1.04,P=0.036) in the death group were significantly higher than those in the survival group.There was no statistically significant difference in gender,age,BMI,preoperative hemoglobin,preoperative neutrophil count,preoperative lymphocyte count,preoperative serum albumin,tumor diameter,CEA and CA199 (all P>0.05).Multivariate analysis showed that LDH 215 U/L (HR=3.064,95% CI:1.179-7.961,P=0.022) and RDW 14.5% (HR=2.372,95% CI:1.004-5.600,P=0.049) were independent indicators affecting the prognosis of patients with CLM undergoing simultaneous radical surgery.ROC curve analysis revealed that the AUC of RDW+LDH (0.814) was higher than that of RDW (0.750) and LDH (0.748),with the cut-off value of 13.7% for RDW and 185 U/L for LDH.The median survival time of the high-risk patients (RDW≥13.7% + LDH≥185 U/L) was 8 months (95% CI:2.5-13.5) compared with 16 months (95% CI:9.8-22.2) in the low-risk patients (RDW<13.7% or LDH<185 U/L),with significant difference (P=0.032). Conclusion RDW≥13.7% + LDH≥185 U/L has good predictive value for the prognosis of patients with CLM undergoing simultaneous radical surgery.