Impact of Staging, Histological Grading, and Racial Background on Lip Cancer Survival in the United States: Insights from the SEER Database (2010-2020)

Lip cancer has a distinct biological behavior within head‑and‑neck oncology, although population‑based survival studies remain scarce. We analyzed data from the United States Surveillance, Epidemiology and End Results (SEER) program to assess the prognostic value of tumor stage, histological grade and race in lip cancer diagnosed during 2010 - 2020. A retrospective cohort of 6,717 invasive lip tumors was extracted from 17 SEER registries. Cause specific survival was estimated using Kaplan-Meier curves and compared with log rank tests. Cox proportional hazards regression generated hazard ratios (HRs) with 95% confidence intervals (CIs). Among 4,273 lip cancer cases with SEER staging, survival varied significantly by disease extent. Localized tumors had a 94% lower risk of cancer-specific death compared to distant/regional metastasis, with median survival times of 97 and 18 months, respectively. Histological grade correlated with survival in univariate but not multivariate analysis (after adjusting for stage and race). White and Asian/Pacific Islander patients had better survival, while AI/AN patients (0.4% of the cohort) showed a significantly elevated risk, warranting further study in this underrepresented group. In this national cohort, disease stage at diagnosis and race were key survival determinants in lip cancer. Localized tumors reduced mortality by 94% versus distant disease. Histological grade added no further prognostic value after accounting for stage and race, underscoring the need for longer follow-up and better registry data.