The effect of treatment package time on locally advanced oral cavity cancer outcomes.

OBJECTIVE(S): To assess the influence of treatment package time (TPT) on overall survival (OS) and event free survival (EFS) in oral cavity cancer (OCC) patients treated with surgery and adjuvant radiation therapy (RT) with or without concurrent chemotherapy (CHT). MATERIALS/METHODS: 354 adult OCC patients treated at a single, high-volume center between 2012-2022 with various pathologic risk features were included. TPT was defined as days from surgery to RT completion. Kaplan-Meier estimates, log-rank p-values, univariable (UVA) and multivariable (MVA) Cox regression analyses were performed to determine the impact of TPT on OS and EFS, and the optimal TPT cutoff. RESULTS: The optimal TPT cutoff was 105 days. TPT < 105 days was significantly associated with improved OS and EFS (p = 0.002 and p = 0.027, respectively) compared to TPT ≥ 105 days. On UVA, factors significantly associated with OS were TPT < 105 days, former/current smoker status, pathologic stage IV, positive perineural invasion (PNI), and extranodal extension (ENE) (all p < 0.05). On MVA for OS, TPT < 105 days, former/current smoker status, pathologic stage IV, and positive PNI (all p < 0.05) remained significant. Factors significantly associated with EFS on UVA were TPT < 105 days, former/current smoker status, pathologic stage IV, positive PNI or ENE, and concurrent CHT (all p < 0.05). On MVA, TPT < 105 days, pathologic stage IV, and positive PNI (all p < 0.05) remained significant. CONCLUSIONS: In a large, homogenous cohort of OCCs, optimal TPT was <105 days, with TPT ≥ 105 days significantly associated with worse OS and EFS. Multidisciplinary coordination should analyze factors potentially contributing to treatment delay.

Improving Radiotherapy Response in the Treatment of Head and Neck Cancer.

The application of radiotherapy to the treatment of cancer has existed for over 100 years. Although its use has cured many, much work remains to be done to minimize side effects, and in-field tumor recurrences. Resistance of the tumor to a radiation-mediated death remains a complex issue that results in local recurrence and significantly decreases patient survival. Here, we review mechanisms of radioresistance and selective treatment combinations that improve the efficacy of the radiation that is delivered. Further investigation into the underlying mechanisms of radiation resistance is warranted to develop not just novel treatments, but treatments with improved safety profiles relative to current radiosensitizers. This review is written in memory and honor of Dr. Peter Stambrook, an avid scientist and thought leader in the field of DNA damage and carcinogenesis, and a mentor and advocate for countless students and faculty.