Comparing the Efficacy and Safety of IC-ICCRT-IO With CT-CCRT for Unresectable Locally Advanced ESCC: A Retrospective Analysis

The present study was designed to evaluate the efficacy and safety of induction chemotherapy combined with a PD-1 inhibitor (sintilimab) followed by concurrent chemoradiotherapy (CCRT) plus sintilimab and subsequent maintenance (IC-ICCRT-IO) in patients with unresectable locally advanced esophageal squamous carcinoma (ESCC) compared with induction chemotherapy followed by CCRT without PD-1 inhibitors (CT-CCRT) using propensity score matching (PSM). Data collected from patients with histologically confirmed, inoperable ESCC treated with IC-ICCRT-IO or CT-CCRT were retrospectively analyzed—a 1:1 PSM with a caliper of 0.05 balanced potential biases. Treatment effects and adverse events (AEs) were assessed using imaging, medical records, and follow-up. Primary endpoints were median progression-free survival (PFS) and PFS rates at 12 and 18 months. Secondary endpoints included overall survival (OS), response rates, and safety. The results showed that t he PSM produced 27 comparable pairs; the median follow-up was 20.5 months. IC-ICCRT-IO significantly improved PFS (median not reached, 12 mo rate: 96.6% vs. 80.5%; 18 mo rate: 85.2% vs. 63.0%, P =0.011) and OS (median not reached, 12 and 18 mo rate: 100% vs. 88.9%, P =0.007). Objective response rates were 88.9% versus 48.1% ( P =0.003). Grade ≥3 AEs occurred in 55.6% versus 44.4% ( P =0.586), primarily nonimmune-related. Severe immune-related rash and radiation pneumonitis were rare and manageable. The results suggested that IC-ICCRT-IO shows promise as an effective, safe treatment for unresectable, locally advanced ESCC. Prospective studies are needed to confirm these findings.