164P - Neoadjuvant immune checkpoints inhibitors plus chemoradiotherapy for patients with locally advanced esophageal squamous cell carcinoma

Background

Immune checkpoint inhibitors (ICI) were demonstrated to extend survival in patients with metastatic esophageal squamous cell carcinoma (ESCC). However, the role of ICI in locally advanced ESCC is not yet established. Herein, we conducted a retrospective study to evaluate the efficacy and safety of ICI plus neoadjuvant concurrent chemoradiotherapy (CCRT) for patients with locally advanced ESCC.

Methods

ESCC patients treated with neoadjuvant CCRT were retrospectively recruited into our study. Patients were classified into ICI-CCRT and CCRT according to regimens during CCRT. ICI-CCRT referred to ICI plus chemoradiotherapy while CCRT referred to chemoradiotherapy alone. Kaplan-Meier curves were estimated for recurrent-free survival (RFS) and overall survival (OS).

Results

A total of 150 patients were enrolled into our study, with 43 patients in ICI-CCRT and 107 patients in CCRT group. The median age was 58.5 years old of our patients and median follow-up period were 22 months. As for patients in ICI-CCRT, 33 patients received nivolumab plus CCRT and 10 patients received pembrolizumab plus CCRT. The median RFS was not reach (NR) versus 16.2 months in ICI-CCRT and CCRT group, respectively (p= 0.016). The median OS was not reach (NR) versus 20.0 months in ICI-CCRT and CCRT group, respectively (p= 0.002). The response rates were significantly higher in IC-CCRT, accounting for 74 % versus 65 % in ICI-CCRT arm and CCRT arm, respectively. Multivariate analysis showed ICI-CCRT was an independent predictor associated with survival. Grade 3/4 adverse events were comparable between each group.

Conclusions

Neoadjuvant ICI-CCRT is superior to CCRT for locally advanced ESCC patients with similar toxicity profiles. Further prospective studies are warranted to validate our conclusions.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.