Efficacy and Safety of Concurrent Chemoradiotherapy Combined withNimotuzumab in Elderly Patients with Esophageal Squamous Cell Carcinoma:A Prospective Real-world Pragmatic Study

Background: Concurrent or definitive chemoradiotherapy is the standard treatment of locally advanced esophageal squamous cell carcinoma (ESCC). Elderly patients could not tolerate the standard concurrent chemotherapy and were treated with radiotherapy because of weak physical status and multiple comorbidities. Objective: The efficacy and safety profile of concurrent (chemo) radiotherapy combined with nimotuzumab in elderly patients with ESCC were investigated. Methods: Eligible elderly (≥70 years) patients with locally advanced ESCC were enrolled in this prospective, real-world pragmatic study and received concurrent chemoradiotherapy or radiotherapy combined with nimotuzumab. The primary endpoint was overall survival (OS). Secondary endpoints were objective response rate, disease control rate, progression-free survival (PFS), and adverse drug reactions. Results: Fifty-three elderly patients were enrolled. Thirty-two (60.4%) were treated with radiotherapy combined with nimotuzumab (RT+N), and 21 (39.6%) with concurrent chemoradiotherapy combined with nimotuzumab (CRT+N). The median age was 75.8 years. Fourteen (56.0%) patients achieved a partial response, and 11 (44.0%) patients achieved stable disease at 3 months. The median follow-up duration was 24.4 (95%CI, 21.6-26.7) months. Median OS (mOS) was 27.0 (95%CI, 14.8-48.4) months. Median PFS (mPFS) was 22.6 (95%CI, 12.4-not reached) months. Higher mPFS (not reached vs. 12.0 months; p=0.022) and mOS (48.4 vs. 15.3 months; p=0.009) were observed in the CRT+N group compared with the RT+N group. Most adverse reactions were grade 1-2 (46, 86.8%). Conclusions: Concurrent chemoradiotherapy or radiotherapy combined with nimotuzumab was safe and well-tolerated in elderly patients with locally advanced ESCC. ESCC patients treated with CRT+N could live longer.