Correlation between serum iron level and overall survival of oral cancer

Abstract

To explore the correlation between serum iron(Fe) and the overall survival of oral cancer. Patients with oral cancer who met the inclusion criteria in the Department of Oral and Maxillofacial Surgery of the First Affiliated Hospital of Fujian Medical University from January 2010 to April 2017 were collected. The average age was(57.12±13.94) years old, including 489 males(65.46%), 258 females(34.54%) and 564 cases of squamous cell carcinoma(77.90%). Overall survival rates were calculated by Kaplan-Meier method. Survival difference was compared by log-rank test. Cox regression model was used to estimate the hazard ratio(HRs) and 95% confidence intervals(95%CIs). The distributions of serum iron level were non-normal distribution(P<0.001), and the serum iron level is expressed as 13.9(10.3, 17.8)μmol/L in M(P25, P75). According to X-tile, the optimal cut-off value of serum iron was 15.3 μmol/L, used as a criterion to group patients. The result showed that the mortality risk of patients with oral cancer in high serum iron level(Fe>15.3 μmol/L) was 0.72 times of patients in lower one(Fe≤15.3 μmol/L)(95%CI 0.52-0.99). Stratified analysis suggested that serum iron was a good predictor of patients with oral cancer aged 60 years(HR=0.62, 95%CI 0.39-0.99), male(HR=0.66, 95%CI 0.44-0.98), with TNM stage I-II(HR=0.42, 95%CI 0.20-0.88) and squamous cell of pathological type(HR=0.69, 95%CI 0.49-0.97). Serum iron is closely related to the overall survival of oral cancer, patients with high serum iron have a lower risk of death.