Real-world treatment patterns and overall survival (OS) in locoregionally advanced head and neck squamous cell carcinoma (LA HNSCC) in the U.S.

Abstract

e23275 Background: Multimodal therapy, including definitive radiotherapy (RT) with or without systemic therapy (ST) or surgery followed by adjuvant RT ± ST is typically recommended for patients (pts) with LA HNSCC treated with curative intent. Assessing real-world use of various treatment modalities and OS helps to better understand the unmet needs in this population. Methods: The linked SEER-Medicare data (2007–2019) was used in this retrospective cohort study. Pts with newly diagnosed stage III-IVB (AJCC 6/7th) LA HNSCC (larynx, hypopharynx, oral cavity, or oropharynx) who received primary treatment within 4 months after initial diagnosis were included. HPV status was not available. OS from index date, i.e., primary treatment initiation date, was described using the Kaplan-Meier method. Baseline (12 months prior to index date) factors associated with OS were assessed using a Cox proportional hazards model. Hazard ratios (HRs), 95% confidence intervals (CIs), and p values were reported. Results: In total, 1885 pts met the selection criteria (median follow-up: 24.8 months). The mean age at initial diagnosis was 74.3 years, 67.2% were male, and 81.6% were white. Less than 1/3rd of pts received primary surgery (resected). More than half of resected pts received RT±ST post-surgery. In unresected pts, nearly 2/3rds received definitive concurrent RT+ST. The median OS and 5-year OS were 32.7 months and 37.6%, respectively, for all pts and were comparable between resected and unresected pts. In the multivariable Cox models for both resected and unresected pts, older age, more advanced tumor stage, hypopharynx (vs. oropharynx), and higher Charlson comorbidity index scores were associated with significantly shorter survival. Additionally, surgery followed by RT+ST (vs. surgery only) (HR = 0.50, 95% CI = 0.34-0.72, p < 0.001) and definitive RT+ST (vs. definitive RT only) (HR = 0.69, 95% CI = 0.58-0.81, p < 0.001) were associated with significantly longer survival in resected and unresected pts, respectively. Conclusions: In elderly pts with LA HNSCC, surgery followed by RT and definitive RT+ST were the most common treatment modalities in resected and unresected pts, respectively. The suboptimal real-world survival across all pts with LA HNSCC regardless of treatment strategy highlights a significant unmet need. Studies focused on the novel application and sequencing of effective immunotherapies are needed. Table 1. Primary treatment and OS in LA HNSCC1 [Table: see text]