Survival after neoadjuvant chemotherapy or chemoradiotherapy for resectable esophageal squamous cell carcinoma: A pooled analysis of randomized clinical trials

Background

The comparison of neoadjuvant chemoradiotherapy (nCRT) versus neoadjuvant chemotherapy (nCT) for locally advanced esophageal squamous cell carcinoma (ESCC) remains inconclusive, and the optimal regimen is still under investigation.

Methods

Prospective randomized clinical trials were systematically searched in electronic databases from inception to Oct 2023. A graphical reconstructive algorithm was employed to extract time-to-event outcomes from Kaplan-Meier curves presented in the original studies. Using reconstructed individual patient data, summary overall survival (OS) and disease progression-free survival (DFS) for nCRT versus nCT, primarily doublet chemotherapy were recalculated. Hazard Ratios (HRs) of OS and DFS reported were also pooled by the fixed-effects model.

Results

A total of 6 randomized clinical trials comprising 1162 patients were included in our analysis. In the individual patient data (IPD) pooled analysis, a significant OS benefit was found for nCRT in ESCC (HR=0.81, 95 %CI:0.67–0.98, p=0.029), compared with the treatment of nCT. The median overall survival time were 53 months (95 %CI:41.9–67.7 m) and 66 months(95 %CI:57.2-NA) respectively in the nCT and nCRT groups. Additionally, a significant improvement in PFS for nCRT compared to nCT in the IPD pooled analysis (HR=0.79,95 %CI:0.64–0.98; p=0.027). Consistent with above results, the pooled HRs of OS and DFS for nCRT versus nCT were 0.78 (95 % CI 0.65–0.92, p=0.004) and 0.79 (95 % CI: 0.65–0.97, p=0.02), respectively. Notably, no substantial heterogeneity across studies was observed.

Conclusions

Our findings indicate that nCRT offers better survival outcomes for ESCC, at least when compared to neoadjuvant doublet chemotherapy.This evidence continues to support the clinical practice of employing nCRT in locally advanced resectable ESCC.