Neoadjuvant chemoimmunotherapy in resectable stage IIIA/IIIB non-small cell lung cancer

Background: A small proportion of patients with non-small cell lung cancer (NSCLC) experience objective clinical benefit after neoadjuvant programmed cell death 1 (PD-1) blockade. A neoadjuvant therapeutic regimen combining immune checkpoint blockade with chemotherapy might improve the treatment effect, but such a regimen has not been tested in patients with resectable stage IIIA/IIIB NSCLC.

Methods: A retrospective study of 35 patients with resectable stage IIIA and IIIB NSCLC who were treated with neoadjuvant chemoimmunotherapy (NCIO) was performed. Patients were evaluated for pathological complete response (pCR), major pathologic response (MPR), safety, and feasibility. The correlations of pathologic response with various clinical factors were studied to identify predictors of pathological response.

Results: NCIO was associated with few immediate adverse events. NCIO did not delay planned surgery and led to a pCR rate of 51.43% and an MPR rate of 74.29% for the primary tumor. No association was observed between programmed death-ligand 1 (PD-L1) expression before NCIO and the pathologic response (Pearson's r=-0.071; P=0.685). However, a significant difference was observed in pathological response in patients with intracavitary and extracavitary tumors (P<0.05). Patients with intracavitary type had a higher pCR (76.47% vs. 31.58%) and MPR (100% vs. 50.00%) rate than patients with extracavitary type (Pearson's r=0.7280; P=0.0009).

Conclusions: NCIO was associated with few side effects, did not delay surgery, and achieved a pCR in 51.43% and MPR in 74.29% of resected tumors. No significant correlation was found between pathologic response and PD-L1 expression. While the intracavitary and extracavitary tumors type T was predictive of the pathological response to NCIO.