Investigation of the efficacy and feasibility of combined therapy of PD‐L1‐enhanced exogenous peripatetic adoptive natural killer (NK) cells in combination with antiangiogenic targeted therapy in the treatment of extensive‐stage small cell lung cancer

A 67‐year‐old male patient presented with extensive‐stage small cell lung cancer with the primary lesion located in the right upper lung, accompanied by multiple metastases to the pleura and abdominal cavity with enlarged mediastinal lymph nodes. A combination therapy approach was used to target the patient's multiple systemic metastases after localized radiotherapy. The approach involved adoptive transfer of programmed death ligand 1 (PD‐L1) enhanced exogenous natural killer (NK) cells, along with antiangiogenic treatment. Allogeneic cord blood NK cells were infused back into the patient over two consecutive days. On the first day, the treatment was followed by a dose of 1200 mg of atezolizumab. Subsequently, the patient received a daily dose of 10 mg of anlotinib administered orally for 14 days. This was followed by a 7‐day break, and each cycle lasted 21 days. After delivering localized radiation to the primary lesion in the right lung and metastatic mediastinal lymph nodes, complete remission was achieved in the local lesion, effectively avoiding the risk of superior vena cava syndrome. Following six cycles of combined therapy, most of the metastatic lesions had disappeared, and the remaining metastatic lesions had significantly reduced in size. The recent therapeutic effect resulted in partial remission. The combination therapy of immune checkpoint inhibitor PD‐L1‐enhanced exogenous adoptive transfer NK cells, along with antiangiogenic targeted treatment, demonstrated a satisfactory short‐term effect, with disappearance of most of the metastases and noticeable shrinkage in the remaining metastatic lesions.