Comparative Analysis of Concurrent Chemoradiotherapy Versus Chemotherapy Alone as First-Line Palliative Treatments for Advanced Esophageal Squamous Cell Carcinoma.

: In advanced-stage esophageal squamous cell carcinoma (ESCC), treatment of both the primary tumor and metastatic sites is imperatively required. Consequently, an optimal treatment modality should effectively control both aspects. Therefore, the benefits of concurrent chemoradiotherapy (CCRT) in cases of advanced-stage ESCC should be evaluated. : This retrospective study compared the efficacy and safety of CCRT versus chemotherapy alone for advanced-stage ESCC patients from January 2012 to December 2023 at a university hospital in Southern Thailand. Survival was assessed using the Kaplan-Meier approach, with comparisons being made by the log-rank test. A -value of <0.05 indicated statistical significance. : From a total of 196 patients with stage IV ESCC, 117 (59.7%) received CCRT, while 79 (40.3%) received chemotherapy alone. The median overall survival (OS) time was 9.04 months for CCRT and 5.79 months for chemotherapy (hazard ratio, HR: 0.58 [0.43-0.78]). CCRT significantly improved OS time in stage IVA patients (HR: 0.52 [0.29-0.93]), but not in stage IVB patients (HR: 0.76 [0.51-1.11]). The median progression-free survival (PFS) time was 6.04 months for CCRT and 3.50 months for chemotherapy (HR 0.48 [0.35-0.65]). The objective response rates (ORRs) were 43.6% and 22.8%, respectively ( = 0.003). Hematological toxicities were more common with CCRT, along with mild cases of treatment-associated pneumonitis and dermatitis. : Although palliative chemotherapy is the standard treatment for advanced-stage ESCC, CCRT provides significant benefits for patients with stage IVA ESCC, improving OS, PFS, and ORRs, despite there being a higher incidence of adverse events. Thus, CCRT should be considered for patients with stage IVA ESCC with a good performance status.