(A532) Delays in adjuvant radiation therapy do not alter survival in lip squamous cell carcinoma

Monday, October 13, 2025

12:00 PM - 1:00 PM EDT

Location: OTO EXPO, Posters

Presenting Author(s)

James A. Widner, BS

Medical Student
Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery, Baylor College of Medicine, Houston, Texas, U.S.A.
Houston, Texas, United States

Co-Author(s)

James A. Widner, BS

Medical Student
Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery, Baylor College of Medicine, Houston, Texas, U.S.A.
Houston, Texas, United States
David J. Hernandez, MD

Assistant Professor
Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery, Baylor College of Medicine, Houston, Texas, U.S.A.
Houston, TX, United States
VS

Vlad C. Sandulache, MD, PhD

Associate Professor
Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery, Baylor College of Medicine, Houston, Texas, U.S.A.
Houston, Texas, United States
Ray Y. Wang, MD

Assistant Professor
Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery, Baylor College of Medicine, Houston, Texas, U.S.A.
Houston, Texas, United States

Senior Author(s)

Ray Y. Wang, MD

Assistant Professor
Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery, Baylor College of Medicine, Houston, Texas, U.S.A.
Houston, Texas, United States

Disclosure(s):

James A. Widner, BS: No relevant relationships to disclose.

Vlad C. Sandulache, MD, PhD: No relevant relationships to disclose.

Ray Y. Wang, MD: No relevant relationships to disclose.

Introduction: Time to adjuvant radiation (TTR) within 6 weeks is a quality benchmark in head and neck cancer and delays are broadly associated with inferior outcomes. However, this time cutoff has not been validated in lip squamous cell carcinoma (SCC), which may be less aggressive than SCCs of other head and neck mucosal sites. To evaluate the role of TTR in lip SCC, we examine its association with overall survival (OS) in a cohort of patients from the National Cancer Database (NCDB).

Methods: Retrospective analysis of patients diagnosed with SCC of the lip between 2004 and 2020 who were treated with definitive surgery and adjuvant radiation. Patients were identified using ICD-O site and histology codes for squamous cell carcinoma of the lip. Clinicopathologic measures were compared between groups using Chi-Square tests. Survival was determined using the Kaplan-Meier method and hazard ratios (HR) were calculated from univariate and multivariate Cox proportional hazard regressions.

Results: 982 patients with lip SCC were identified for inclusion, of whom 72% (n=704) experienced delays in adjuvant radiation (TTR > 6 weeks). Most patients in both TTR groups were White males aged 60 or older. A larger proportion of patients experiencing TTR delays had T3/4 disease (p = 0.02) or nodal metastasis (p = 0.003). Delayed TTR was not associated with significantly worse OS (HR: 1.21, 95% CI: 0.97-1.51, p = 0.09); this remained the case in a subgroup analysis of patients with advanced (T3/4) primaries or nodal metastasis. On multivariate analysis, age, Asian race, T classification, N classification, positive surgical margins, and Charlson Comorbidity Index were associated with worse OS; however, TTR of >6 weeks was not (aHR: 0.92, 95% CI: 0.70-1.2, p = 0.57).

Conclusions: Delays in PORT were not associated with worse survival in lip SCC. This finding contrasts with studies in heterogeneous HNSCC patient populations or patients with cancers in other oral cavity sites, highlighting potential variability in treatment sensitivity across HNSCC subtypes.