Postoperative pathological complete response in a patient with PD-L1-negative stage IIIB lung squamous cell carcinoma following neoadjuvant tislelizumab treatment combined with chemotherapy: A case report and literature review

The utilization of immune checkpoint inhibitors in oncological treatment has increased in recent years. The therapeutic strategy of targeting the programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway has altered the management of advanced non-small cell lung carcinoma (NSCLC). Tislelizumab, a novel anti-PD-1 monoclonal antibody developed in China, has demonstrated efficacy in treating advanced NSCLC. However, its potential role as a neoadjuvant therapy for locally advanced NSCLC has not been definitively established. Current guidelines do not specify which patient populations may gain the most benefit from neoadjuvant immunotherapy coupled with chemotherapy, nor do they indicate the optimal timing, dose or duration of adjuvant maintenance therapy post-NSCLC surgery. Similarly, data concerning the safety and practicability of surgical resection following neoadjuvant tislelizumab treatment for NSCLC remain limited. The present study describes the case of a patient diagnosed with stage IIIB NSCLC, which was initially deemed unresectable. A preoperative biopsy of the tumor mass revealed squamous cell carcinoma and a negative PD-L1 gene test. Notably, after two cycles of neoadjuvant tislelizumab treatment coupled with chemotherapy, the tumor exhibited marked shrinkage. This permitted the patient to undergo thoracoscopic radical lung cancer resection, which resulted in a pathological complete response. Postoperative pathology identified a large infiltration of lymphoplasmacytic cells and foamy histiocytes. The patient experienced grade 2 myelosuppression, a condition that was successfully addressed with the administration of recombinant human granulocyte colony-stimulating factor. The present case indicates the safety and feasibility of neoadjuvant immunotherapy integrated with chemotherapy for patients with locally advanced, PD-L1-negative NSCLC prior to surgical intervention. Moreover, the case suggests the potential of this therapeutic combination to alter the tumor microenvironment. However, the generalization of these findings necessitates further validation through randomized multicenter trials.