High-Dose Versus Standard-Dose Intensity-Modulated Radiotherapy With Concurrent Paclitaxel Plus Carboplatin for Patients With Thoracic Esophageal Squamous Cell Carcinoma: A Randomized, Multicenter, Open-Label, Phase 3 Superiority Trial

Abstract

The standard dose (SD) of definitive concurrent chemoradiotherapy (dCRT) remains 50.4 Gy in patients with esophageal cancer; a higher dose, when applied with conventional radiation therapy techniques, increases toxicities without improving survival. We investigated whether a high dose of 59.4 Gy using intensity-modulated radiation therapy (IMRT) would improve survival without increasing toxicities. Patients with inoperable thoracic esophageal squamous cell carcinoma (SCC) referred for dCRT were randomly assigned (1:1) to high-dose (HD) IMRT (59.4 Gy) or SD IMRT (50.4 Gy). Chemotherapy consisted of 6 cycles of concurrent weekly paclitaxel and carboplatin and a maximum of 2 cycles of consolidation chemotherapy. Nutritional intervention was implemented for patients with malnutrition on the basis of nutritional screening. The primary endpoint was median overall survival (mOS). Analyses were by modified intention to treat. Between April 30, 2016, and April 30, 2019, 167 patients were enrolled at 9 participating centers in China. Seventy-one patients in the HD and 73 patients in the SD groups were included in the analysis; 86.8% of the patients completed radiation therapy and 70.1% received 5 or 6 cycles of concurrent chemotherapy. The median follow-up was 36.0 months. The mOS was 28.1 and 26.0 months in the HD and SD arms, respectively (P=.54). A total of 7 treatment-related deaths were observed. Grade 3 or worse treatment-related toxicities were observed in 62% and 68.5% of the patients in the HD and SD arms, respectively (P=.675). For patients with inoperable thoracic esophageal SCC, a dose of 59.4 Gy did not improve survival compared with the SD of dCRT using IMRT.