Definitive radiotherapy for early stage hypopharyngeal cancer (T1–2N0M0): a retrospective study of clinical outcomes and prognostic factors

Hypopharyngeal carcinoma (HPC) is an aggressive malignancy that is often diagnosed at an advanced stage. Advances in narrowband imaging have increased the early detection rate of HPC. Definitive radiotherapy (RT) is a noninvasive, organ-preserving option recommended for early stage (T1-2N0M0) disease; however, its clinical outcomes remain limited. This study retrospectively evaluated the clinical outcomes of definitive RT for early stage HPC. We retrospectively analyzed 55 patients with early stage HPC who were treated with RT between 2013 and 2023. Treatments included volumetric-modulated arc therapy or three-dimensional conformal radiotherapy with elective nodal irradiation. Chemoradiotherapy was administered to selected patients with stage T2 disease. Survival outcomes were assessed using Kaplan-Meier and Cox models. Median follow-up was 43 months. The 5-year overall survival (OS), progression-free survival, and cancer-specific survival rates were 65%, 57%, and 82%, respectively. Local control, locoregional control and laryngeal preservation rate at 5 years were 79%, 74%, and 91%, respectively. Initial recurrences were locoregional, with local recurrence in 10 of 55 patients (18%) and regional lymph node recurrence in three of 55 patients (5.4%). In univariate analysis, older age (≧71 years) and a history of esophageal cancer were associated with significantly worse OS. The multivariate analysis confirmed that older age and a history of esophageal cancer were independent predictors of OS. RT for early stage HPC provides favorable oncological outcomes and high rates of laryngeal preservation. However, OS was strongly influenced by age and a history of esophageal cancer, highlighting the need for treatment selection and follow-up, including surveillance for second primary esophageal cancer.