Neoadjuvant Chemotherapy or Neoadjuvant Chemoradiotherapy for Patients with Esophageal Squamous Cell Carcinoma: Real-World Data Comparison from A Japanese Nationwide Study.

Background: Although neoadjuvant treatment has become the standard of care for patients with locally advanced esophageal cancer, previous studies comparing neoadjuvant chemotherapy (NAC) and neoadjuvant chemoradiotherapy (NACRT) have demonstrated inconclusive results.
Methods: Our study cohort included 3978 patients from 85 institutions. Those who underwent NAC or NACRT followed by surgery for esophageal squamous cell carcinoma (ESCC) were eligible for inclusion. We used the inverse probability of treatment weighting (IPTW) method to compare the outcomes between NAC and NACRT.
Results: Among the 3978 patients, 3777 (94.9%) received NAC and 201 (5.1%) received NACRT. After IPTW adjustment, the NACRT group had more patients with pathologically downstaged diseases and significantly better pathological response compared with the NAC group (p < 0.001); however, 5-year overall survival (OS), recurrence-free survival (RFS), and regional recurrence-specific survival (RRSS) were comparable between the groups. Subgroup analysis stratifying patients according to cT category showed that among cT1-2 patients, those in the NACRT group had significantly longer 5-year OS, RFS, and RRSS than those in the NAC group (P = 0.024, < 0.001, and 0.020, respectively). In contrast, no significant differences were observed among cT3-4a patients. The competing risks regression model showed comparable subdistribution hazard ratios for 10-year cancerous and noncancerous deaths between the NAC and NACRT groups.
Conclusions: Compared with NAC, NACRT for ESCC did not promote better survival despite better therapeutic effects and did not increase noncancerous deaths.
(© 2023. Society of Surgical Oncology.)