High-Dose Radiotherapy for Cervical and Upper Thoracic Esophageal Cancer: A Multicenter Real-World Study with Dose-Benefit Exploration

The optimal radiotherapy dose for cervical and upper thoracic esophageal cancer (ESCA) remains controversial, with limited evidence supporting dose escalation. This study aims to evaluate the survival impact of varying radiotherapy doses and explore potential benefits in specific patient subgroups using multicenter real-world data.Data from 2,527 inoperable cervical and upper thoracic ESCA patients treated with IMRT/3DCRT across eight medical centers in China during 1st June 2004 and 1st June 2020 were retrospectively analyzed. Patients were divided into low-dose (50–<60 Gy) and high-dose (≥ 60 Gy) groups. Subgroup analyses were conducted to identify populations that might benefit from higher doses.High-dose radiotherapy (≥ 60 Gy) improved overall survival (OS) in cervical ESCA patients before and after propensity score matching (P = 0.026 and P = 0.047). For upper thoracic ESCA, high-dose radiotherapy showed a survival advantage before matching (P = 0.008), though not after (P = 0.680). Subgroup analysis revealed survival benefits in upper thoracic ESCA patients with poor performance status (KPS < 90), those not receiving chemotherapy (P = 0.043 and P = 0.013), and borderline improvement in patients with smaller gross tumor volumes (< 35.1 cm³, P = 0.057). Radiation doses exceeding 63 Gy provided no additional survival benefit compared to 60–63 Gy.High-dose radiotherapy (≥ 60 Gy) significantly improves survival in cervical ESCA patients. Subgroup analysis highlights its potential benefits for upper thoracic ESCA patients with KPS < 90, those not receiving chemotherapy, and those with smaller tumor volumes (< 35.1 cm³).