1452P - Camrelizumab plus chemotherapy combined with consolidative radiotherapy as first-line treatment for oligometastatic esophageal squamous cell carcinoma (ESCORT-1ST-RT): A single-arm, open-label, phase II trial

Background

Compared to chemotherapy alone, immunotherapy combined with chemotherapy as the first-line standard treatment for esophageal squamous cell carcinoma (ESCC) can increase progression-free survival (PFS) to 5.8-7.2 months. This study aimed to explore the feasibility and safety of combining camrelizumab and chemotherapy with consolidative radiotherapy in the treatment of advanced oligometastatic ESCC.

Methods

This study included newly diagnosed patients with stage IV ESCC confirmed by histopathology and imaging examination who had ≤ 5 metastatic lesions in ≤ 3 organs. All patients were treated with camrelizumab combined with albumin paclitaxel and carboplatin for 4 cycles, followed by consolidative radiotherapy. The primary esophageal lesion and metastatic lymph nodes were treated with involved-field irradiation therapy,. For distant metastases in organs, radiotherapy was tailored to individual clinical needs. The maintenance duration of camrelizumab treatment was limited to a maximum of 12 months. The primary endpoint was PFS.

Results

From October 26, 2021, to September 28, 2022, 29 patients with ESCC, median age 63 (range 51-74), were enrolled; 93.1% were male. 27 (93.1%) patients completed planned radiotherapy. Of 29 evaluated patients, 23 achieved an objective response and 6 maintained stable disease. the ORR and DCR were 79.3% (95% CI 78.2-80.4) and 100% (95% CI 100-100), respectively. With 23.3 months (95%CI 21.5-25.1) of follow-up, the median PFS was13.7 months (95% CI 9.9-17.5), the median OS has not reached and the 1-year and 2-year OS rates were 72.4% (95% CI 52.3-85.1) and 61.4% (95% CI 41.1-76.5), respectively. 1 patient discontinued camrelizumab treatment due to radiation esophagitis. No grade 5 TEAEs occurred.

Conclusions

Consolidative radiotherapy following camrelizumab combined with chemotherapy showed potential efficacy and manageable tolerability in patients with advanced oligometastatic ESCC,The mPFS is much higher than the combination of immunotherapy and chemotherapy, and still needs to be validated through large-scale RCT study.

Clinical trial identification

ChiCTR2400079514.

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.