Objective
To assess prognostic factors of patients with operable oral cavity squamous cell carcinoma (OSCC), focusing on the associations with smoking/alcohol exposure and age.
Materials and Methods
A total of 247 patients with OSCC who received curative surgery ± adjuvant radiotherapy were analyzed. The patient subgroups were divided according to pretreatment smoking/alcohol exposure. Individuals aged 45 years or less were classified as younger patients.
Results
The median follow‐up was 52.2 months. The 5‐year locoregional progression‐free survival (LRFFS), distant metastasis‐free survival (DMFS), overall survival (OS), and cancer‐specific survival (CSS) rates were 85.2%, 88.3%, 78.1%, and 83.5%, respectively. An advanced stage, differentiation, and lympho‐vascular space invasion were significantly associated with lower OS and CSS. In a subgroup analysis of younger patients (n = 49), more smoking/alcohol exposure was significantly associated with better OS (hazard ratio [HR]: 0.21, 95% confidence interval [CI]: 0.05–0.95, p = .043). With increasing age, the HR for smoking/alcohol exposure with respect to OS increased up to 11.59 (95% CI: 1.49–89.84, p = .019) in older patients.
Conclusion
Younger OSCC patients with non‐ or less smoking/alcohol exposure showed unfavorable outcomes. The prognostic significance of pretreatment smoking/alcohol exposure changed from favorable to detrimental with increasing age in operable OSCC.