The impact of preoperative glycated hemoglobin levels on outcomes in oral squamous cell carcinoma

Objectives: This study aimed to investigate the association between preoperative glycated hemoglobin (HbA1c) levels and the treatment outcomes of oral cavity squamous cell carcinoma (OSCC). Methods: Three hundred and fifty-eight OSCC patients were consecutively enrolled between July 2004 and July 2016. Clinicopathological parameters and survival outcomes were analyzed following HbA1c stratification of 6.5% (HbA1c ≥ 6.5%: n = 74, 20.6%) and 7.0% (HbA1c ≥ 7.0%: n = 53, 14.8%). Results: Higher HbA1c levels were associated with elevated body mass index, lower albumin levels, wider surgical margins, and prolonged hospital stays (HbA1c 6.5%: p =.001,.048,.030,.009, respectively; HbA1c 7.0%: p =.092,.032,.009,.015, respectively). Survival rates stratified by HbA1c 6.5% were as follows: locoregional recurrence-free survival, p =.014; distant metastasis-free survival, p =.013; second primary cancer-free survival, p =.015; overall survival, p =.014; disease-specific survival, p =.002 and HbA1c 7.0%: locoregional recurrence-free survival, p =.013; distant metastasis-free survival, p =.013; second primary cancer-free survival, p =.014; overall survival, p =.015; disease-specific survival, p =.004. Multivariate analyses identified HbA1c as an independent prognostic factor for overall and disease-specific survival (HbA1c 6.5%: p =.014 and.002, respectively; HbA1c 7.0%: p =.036 and.013, respectively). Conclusions: Oral squamous cell carcinoma patients with higher preoperative HbA1c levels had longer hospitalization and worse survival outcomes.