Neoadjuvant Programmed Cell Death Protein 1 Blockade Combined With Stereotactic Body Radiation Therapy for Stage III(N2) Non-Small Cell Lung Cancer: A Case Series

Abstract

The addition of radiotherapy in neoadjuvant chemotherapy did not improve event-free or overall survival in resectable non-small cell lung carcinoma (NSCLC). Neoadjuvant immunotherapy produced major pathologic response(MPR) rate of up to 45%. The potential synergy between radiotherapy and immunotherapy has been described in several studies. We reported outcomes of three cases of stage III/N2 NSCLC treated with neoadjuvant immunotherapy and stereotactic body radiation therapy (SBRT) in a single center. This explanatory trial included treatment-naive patients with stage III resectable NSCLC who received two doses of the programmed cell death protein 1 (PD-1) inhibitor toripalimab after 1 week of receiving SBRT for lung lesions. Thereafter, surgery was planned 4-6 weeks after the second dose. The primary endpoints were safety and feasibility, while the secondary endpoint was the pathologic response rate. Toripalimab combined with SBRT as a neoadjuvant treatment had well-tolerable side effects and did not lead to a delay in surgery. Among the included patients, one achieved pathologic complete response (PCR), one achieved MPR, and one with 20% residual tumor did not achieve MPR. There were few side effects of toripalimab combined with SBRT as a neoadjuvant treatment, and the treatment did not cause a delay in surgery. This study preliminarily explored the outcomes of a new neoadjuvant treatment.

Keywords: Neoadjuvant; non-small cell lung carcinoma; programmed cell death protein 1(PD-1); radiation therapy; stereotactic body radiotherapy (SBRT).