Different pathologic responses to neoadjuvant anti-PD-1 in primary squamous lung cancer and regional lymph nodes
Yun Ling, Ning Li, Lin Li, Changyuan Guo, Jiacong Wei, Pei Yuan, Fengwei Tan, Xiuli Tao, Shuhang Wang, Zhijie Wang, Ning Wu, Jie Wang, Jianming Ying, Shugeng Gao, Jie He
Abstract
Neoadjuvant immunotherapy provides a unique opportunity for understanding therapeutic responses. We analyzed pathologic responses in surgical specimens obtained from 31 squamous non-small cell lung cancer (NSCLC) patients receiving neoadjuvant anti-PD-1 treatment. Fifteen (48.4%) patients achieved pathologic complete response (pCR) or major pathologic response (MPR). Among them, seven (46.7%) were assessed as radiological partial response and eight (53.3%) as stable disease. Among 20 patients with pathologically identified tumor beds in lymph nodes (LNs), 10 and six patients achieved pCR/MPR in primary tumors and paired LNs, respectively. pCR was achieved in 6/19 N1 nodes and 1/7 N2 nodes. Residual viable tumor (RVT) cells in 8/9 MPR specimens had 100% immune-activated phenotype, while a median of 80% of RVT cells in pathologic nonresponse specimens presented immune-excluded/desert phenotype. These findings demonstrated that assessment of pathologic responses in both primary tumor and LNs may be important as a surrogate for assessing neoadjuvant immunotherapeutic efficacy.