Prognostic Significance of the Preoperative Hematological Parameters in Non-Metastatic Rectal Cancer Patients Undergoing Neoadjuvant Chemoradiotherapy and Radical Surgery

Background: Preoperative chemoradiotherapy followed by radical resection is the standard treatment for locally unresectable rectal cancer.This study evaluated the prognostic relationship between preoperative hematological parameters and overall survival among rectal cancer patients receiving trimodal therapy.Methods: From January 2010 to December 2018, 96 patients with primary non-metastatic locally advanced rectal cancer underwent preoperative chemoradiotherapy followed by radical surgery at our institution.The patients' demographic characteristics, clinical and pathological variables, and hematologic parameters were collected retrospectively by reviewing medical records.The Cox proportional hazard model and Kaplan-Meier curve analysis were used to assess overall survival.The receiver operating characteristic curve with the Youden index was used to dichotomize continuous variables. Results:The median age was 58 years, with male predominance (72.9%); 74.0% were in the clinical T3 stage.All patients completed chemoradiotherapy to the whole pelvis and pelvic lymph nodes.Threedimensional conformal radiation therapy, intensity-modulated radiation therapy, and volumetric-modulated arc therapy were included in the study.All patients underwent surgical intervention 12 weeks after completing radiotherapy.The median OS for all patients was 65.0 (range, 7.0-138.0)months.The 3-year OS rate was 85.4% of all patients.Univariate analysis showed that preoperative white blood cell count (>5,200/μL vs. ≤5,200/μL, P=0.004), hemoglobin (P=0.030),peripheral platelet count (>217×10 3 /μL vs. ≤217×103 /μL, P=0.002), increased absolute neutrophil count (P=0.002),increased neutrophil-to-lymphocyte ratio (P=0.027)and a systemic immune-inflammation index (>656×10 9 /L vs. ≤656×10 9 /L, P=0.008) were associated with poor overall survival.On multivariate analysis, a preoperatively high systemic immune-inflammation index (P=0.016)and low hemoglobin levels (P=0.040)remained associated with reduced overall survival.Conclusions: Preoperative counts of white blood cells, peripheral platelets, absolute neutrophils, and the neutrophil-to-lymphocyte ratio and systemic immune-inflammation index were poor prognostic markers for overall survival in rectal cancer patients receiving radical surgery after preoperative chemoradiotherapy.However, a high preoperative hemoglobin level might predict a better prognosis, and the systemic immune-inflammation index might accurately predict survival outcomes in patients with rectal cancer after preoperative chemoradiotherapy.