According to the SCIENCE trial, neoadjuvant chemoradiotherapy with or without sintilimab significantly improved the pathological complete response (pCR) rates compared with neoadjuvant chemotherapy with sintilimab among patients with locally advanced esophageal squamous cell carcinoma.
 
These data were first reported by Xuefeng Leng, MD, Sichuan Cancer Hospital & Institute, Chengdu, China, at the 2025 American Society of Clinical Oncology (ASCO) Gastrointestinal Cancers Symposium.
 
This multicenter, phase 3 trial enrolled 146 patients with locally advanced thoracic esophageal squamous cell carcinoma who had not received any prior treatment. Patients were randomized on a 1-to-1-to-1 basis to receive 2 cycles of neoadjuvant chemotherapy plus sintilimab (arm A, n = 46), sintilimab plus neoadjuvant chemoradiotherapy (arm B, n = 45), or concurrent neoadjuvant chemoradiotherapy alone (arm C, n = 55). Surgical resection was planned for 6 to 8 weeks following completion of neoadjuvant treatment. The coprimary end points were pCR rate and event-free survival.
 
All patient completed neoadjuvant treatment and went on to surgery, achieving a 100% R0 resection rate. The pCR rate was 13% in arm A, 60% in arm B, and 47.3% in arm C. The pCR rates in both arm B and arm C were significantly higher than arm A (arm B vs arm A, difference 47%, odds ratio [OR] = 10, P < .0001; arm C vs arm A, difference 34.2%; OR = 6; P = .0005). Treatment-emergent adverse events grade ≥3 during neoadjuvant treatment were experienced by 8.7% of patients in arm A, 31.1% in arm B, and 36.4% in arm C. There were no perioperative deaths.
 
Dr Leng et al, concluded these results demonstrate neoadjuvant chemoradiotherapy with or without sintilimab “significantly enhances pCR rates compared to [neoadjuvant chemotherapy] with sintilimab” adding that ongoing monitoring of event-free survival is “necessary to validate these results.”

Source:

Leng X, He W, Lyu J, et al. Preliminary results from the multicenter, randomized phase III trial (SCIENCE): Comparing chemotherapy plus sintilimab and chemoradiotherapy plus sintilimab versus chemoradiotherapy for neoadjuvant treatment in resectable locally advanced esophageal squamous cell carcinoma. Presented at 2025 ASCO Gastrointestinal Cancers Symposium. January 23-25, 2025; San Francisco, CA. Abstract LBA329.