Neoadjuvant immunochemotherapy for locally advanced esophageal squamous cell carcinoma: Pooled results analysis from two prospective single-arm phase 2 trials.

Abstract

e16111 Background: The long-term survival data for patients with locally advanced esophageal squamous cell carcinoma receiving neoadjuvant immunotherapy are not available. A pooled analysis of two prospective studies was conducted in this study to investigate the relationship between baseline PD-L1 expression levels, pathological remission after neoadjuvant chemoimmunotherapy, and DFS and OS in patients with locally advanced esophageal squamous cell carcinoma (LA ESCC). Methods: This study included clinical resectable IIB-IVA ESCC patients from two phase 2 trials (NCT05302011, NCT04568200). Patients received neoadjuvant ICI (Durvalumab or Pembrolizumab) combined with chemotherapy (docetaxel plus cisplatin or carboplatin) every 3 weeks for 4 cycles before surgery. The primary endpoint was the pathological complete response rate (pCR) and the radical resection rate (R0). Results: From May 2020 to July 2024, 57 patients received treatment and 45 underwent surgery with 100% R0 resection. The median age is 65. 46(80.7%) patients were male. The number of stage II,III,IIVA and IVB were 2,13,38 and 4, separately. There were 22 patients(38.6%) shown PD-L1 expression CPS≥10. 30(52.6%) patients accepted Pembrolizumab and 27 (47.7%) patients accepted Durvalumab.All patients completed neoadjuvant therapy with an ORR of 71.9% (41/57) and DCR of 98.2%. The CAP0/1/2/3 rates were 22.2%, 20%, 20%, and 37.8%, respectively. At a median follow-up of 24.3 months, the 1-year EFS rate in CAP 0/1 and CAP 2/3 groups was 100% and 92.3%, and the 2-year EFS rate was 100% and 73%. The 1-year OS rate was 100% and 92.3%, and the 2-year OS rate was 100% and 87.2%. The mEFS for CPS≥10 and CPS＜10 groups was not reached and 30.5 months, the OS was not reached in each group. No new adverse events were observed and the treatment regimen was safe and tolerable. Conclusions: The combination of neoadjuvant immune-chemotherapy has achieved satisfactory efficacy and safety results in locally advanced ESCC. Patients who achieved pathological CAP0/1 had better EFS and OS rates than others. Clinical trial information: NCT05302011 ; NCT04568200 .