Does lymphovascular invasion predict survival in oral cancer? A population-based analysis

Abstract

ObjectiveTo evaluate lymphovascular invasion as an independent predictor for overall survival in patients with oral cavity squamous cell carcinoma. Study DesignRetrospective cohort study. SettingMulti-center, population-based facilities reporting to the National Cancer Database registry. MethodsThe database was accessed to collect data on patients with oral cavity squamous cell carcinoma. A multivariate cox proportional hazards model was used to analyze the association between presence of lymphovascular invasion and overall survival. Results16,992 patients met inclusion criteria. 3,457 patients had lymphovascular invasion. The mean follow-up was 32 ± 19 months. Lymphovascular invasion predicted reduced 2-year overall survival (relative hazard 1.29, 95% CI: 1.20, 1.38, p < 0.001) and 5-year overall survival (relative hazard 1.30, 95% CI: 1.23, 1.39, p < 0.001). LVI reduced overall survival in patients with squamous cell carcinoma of the oral tongue (HR: 1.27, 95% CI: 1.17, 1.39, p < 0.001), floor of mouth (HR: 1.33, 95% CI: 1.17, 1.52, p < 0.001) and buccal mucosa (HR: 1.44, 95% CI: 1.15, 1.81, p = 0.001). Patients with lymphovascular invasion treated with surgery plus post-operative radiotherapy had significantly improved survival compared to those who underwent surgery alone (relative hazard 1.79, 95% CI: 1.58, 2.03, p < 0.001), and patients treated with surgery + post-operative chemoradiotherapy had improved survival compared to those treated with surgery alone (relative hazard 2.0, 95% CI: 2.26, 1.79, p < 0.001). ConclusionLymphovascular invasion is an important independent risk factor for decreased overall survival in oral cavity squamous cell carcinoma involving the oral tongue, floor of mouth and buccal mucosa subsites.