Ascertaining the impact of adjuvant radiotherapy in early stage risk factor positive oral cavity squamous cell carcinoma and evaluating patterns of failureA project of theYoung Investigators Committee under the auspices of the Head and Neck Inter Group

The purpose of this retrospective study is to investigate the difference in disease outcomes of patients who were treated with surgery plus adjuvant radiotherapy versus surgery alone for early-stage oral cavity squamous cell carcinoma (OC-SCC) with various risk factors. Currently, surgery is often used as the sole treatment modality of choice for patients with stage I and II OC-SCC. However, certain poor pathological features, such as higher worst pattern of invasion (WPOI), perineural invasion, and lymphovascular invasion, are associated with worse tumor biology and increase the risk of local recurrence, even in the early stages of oral cavity cancer. We seek to investigate whether patients with such high-risk features stand to gain benefit by receiving post-operative radiation therapy (PORT) in an effort to lower the risk of local recurrence, and potentially to improve overall survival. We also seek to learn more about patterns of spread, such as whether particular pathological features increase the chance of contralateral neck nodal failure