Neoadjuvant camrelizumab combined with radiotherapy as a chemotherapy-sparing approach for resectable locally advanced esophageal squamous cell carcinoma: a phase II clinical trial (ESOCORT-NIRT).

Abstract

Camrelizumab combined with radiotherapy may offer an effective neoadjuvant option for locally advanced esophageal squamous cell carcinoma while reducing chemotherapy-related toxicity. We assessed the efficacy and safety of this chemotherapy-sparing regimen. In this single-arm phase II trial, adults with resectable thoracic esophageal squamous cell carcinoma received camrelizumab 200 mg intravenously every 3 weeks for two cycles, concurrently with radiotherapy to 41.4 Gy in 23 fractions, followed by esophagectomy 4-8 weeks later. The primary endpoint was major pathologic response (≤ 10% residual viable tumor) among patients undergoing resection. Secondary endpoints were R0 resection rate, pathologic complete response, treatment-related adverse events, postoperative complications, and survival outcomes. ClinicalTrials.gov NCT05176002. Twenty-five patients were enrolled; three did not undergo surgery (one radiographic complete response with refusal of surgery, one disease progression, and one withdrawal). Twenty-two patients (88%) had esophagectomy, all with R0 resection. Major pathologic response occurred in 12 of 22 patients (54.5%), including pathologic complete response in 8 (36.4%). No grade 3 or higher treatment-related adverse events were observed; the most frequent toxicities were low-grade radiation esophagitis, leukopenia, dermatitis, and hypothyroidism. Postoperative complications were low grade. At a median follow-up of 36 months, five recurrences were recorded, with survival comparable to historical standard neoadjuvant cohorts. Neoadjuvant camrelizumab plus radiotherapy showed low toxicity, pathologic tumor regression, and favorable postoperative outcomes in resectable esophageal squamous cell carcinoma. This chemotherapy-sparing approach may be an alternative for patients who are unsuitable for or intolerant of standard chemotherapy-based neoadjuvant regimens.