Allergy History and Immunotherapy Response in Patients With Recurrent/Metastatic Head and Neck Squamous Cell Carcinoma

ObjectiveThis study examines the association between patient-reported allergy history and immune checkpoint inhibition (ICI) response in patients with recurrent or metastatic head and neck squamous cell carcinoma (RMHNSCC).Study DesignRetrospective cohort study.SettingAcademic tertiary care hospital.MethodsData were collected from the electronic medical records on baseline age, sex, allergy history, human papillomavirus status, T-stage, N-stage, smoking status, and survival for patients with and without an allergy history. The primary outcome was ICI response defined as complete or partial response by the RECIST criteria. Chi-square and logistic regression analyses were conducted to compare rates and odds of ICI response. Kaplan-Meier analyses were used to compare survival between groups.ResultsOur study included 52 patients with an allergy history and 36 patients without an allergy history. The groups were similar in age, sex, HPV status, smoking status, and T- and N-stage. Patients with an allergy history (17/52, 32.1%) had a greater ICI response rate than patients without allergy history (4/36, 11.1%) (P = .02). After adjusting for HPV, patients with allergies had 3.93 (1.19-13.00) times increased odds of ICI response compared to patients without allergies. The median progression-free survival was 6.0 and 4.2 months for patients with and without an allergy history respectively (log-rank, P = .04). The median overall survival was 25.0 and 11.1 months for patients with and without an allergy history respectively (log-rank, P = .002).ConclusionPatient-reported allergy history was associated with ICI response in patients with RMHNSCC, underscoring the potential clinical utility of allergy history in estimating ICI response.