Elevated red blood cell distribution width predicts poor prognosis in patients with oral squamous cell carcinoma

Although red blood cell distribution width (RDW) has been reported to reflect inflammation and nutritional status and to predict prognosis in several different types of cancer, little is known about how RDW might be related to oral squamous cell carcinoma (OSCC). The present study aimed to investigate the prognostic value of preoperative RDW in OSCC patients.

We included 236 OSCC patients from Jinan Stomatological Hospital (Shandong, People's Republic of China) in this retrospective study. All enrolled patients were divided into 2 groups: high RDW (≥15%) and low RDW (<15%) according to the detected RDW values. The correlation of RDW and clinical characteristics was explored, and the prognostic significance of RDW evaluated using Kaplan-Meier curves, log-rank analysis, and the Cox proportional hazards model.

The pretreatment median RDW among all OSCC patients was 14.4%, with a range from 11.6% to 24.5%. The RDW was found to be significantly correlated with node metastasis, tumor length, and TNM stage (P<0.05 for all). As for biochemical parameters, the results showed that higher RDW values were significantly associated with hemoglobin, mean corpuscular volume, white blood cell count, albumin, and C-reactive protein (P<0.01 for all). A significant association of RDW with the tumor marker cytokeratin 19 fragments (CYFRA21-1) and squamous cell carcinoma antigen (SCC-Ag) was also observed (P=0.02, and P=0.03; respectively). Moreover, patients with higher RDW were more likely to receive postoperative therapy (P=0.02). Kaplan-Meier survival curves showed that a high RDW was significantly associated with poor overall survival (OS) (P<0.01), especially in the early stages (I-II). Multivariate analysis revealed that an elevated RDW at diagnosis was an independent prognostic factor for shorter OS (HR =1.46, 95% CI: 1.13-2.86) after adjustment for other cancer-related prognostic factors.

These data suggest that an elevated preoperative RDW (≥15%) at diagnosis may independently predict poorer OS in patients with OSCC, but better-designed studies in the future should be performed to further confirm the value of monitoring RDW.