Metronomic therapy as a favorable independent factor for survival in high-risk oral cavity squamous cell carcinoma.

Abstract

e18022 Background: Oral cavity squamous cell carcinoma (OCSCC) is the largest subpopulation of head and neck squamous cell carcinoma in Taiwan. However, for the high-risk OCSCC, rare patients could achieve long-term survival. The role of metronomic therapy to improve survival after curative therapy is unknown. Methods: This was a single-institute retrospective cohort study. The patients with newly diagnosed high-risk OCSCC from May 2010 to March 2020 were retrospectively enrolled. All patients were divided into groups with and without metronomic therapy. For the group with metronomic therapy, oral tegafur-uracil was administered at a daily dose of 100-400mg per day, 28 days per month, and for one year after completing adjuvant chemoradiotherapy. Cox proportional hazards regression and Kaplan–Meier survival curves were employed for analysis. Results: A total of 220 newly diagnosed high-risk OCSCC patients were retrospectively enrolled, and 46.8% (103/220) of all belonged to the groups with metronomic therapy. The group with metronomic therapy was significantly better in locoregional-free survival (LRFS) and overall survival (OS) than the group without (5-year LRFS, with and without metronomic therapy, 62% and 44%, P = 0.002; 5-year OS, 69% and 47%, P < 0.001). After adjusting with other clinicopathological factors, metronomic therapy was also an independent favorable prognostic factor for both LRFS and OS. In subgroup analysis, metronomic therapy seemed more suitable for patients with extracapsular spread, positive margins, and advanced depth of invasion. Conclusions: Metronomic therapy significantly improved survival for high-risk OCSCC patients after completing curative therapy. Prospectively study is needed to be warranted.