Abstract
Pulmonary large cell neuroendocrine carcinoma (LCNEC) has a poor prognosis, and there is no consensus on optimal treatment strategies for pulmonary LCNEC. Certain patients with pulmonary LCNEC may benefit from targeted and traditional programmed cell death protein-1 (PD-1) monoclonal antibody therapies, however, for most patients, only a few drugs are effective after chemotherapy. The present report describes the case of a 68-year-old man with advanced pulmonary LCNEC treated with cadonilimab and anlotinib after becoming resistant to PD-1 monoclonal antibody therapy and multiple chemotherapies. Computed tomography was used to evaluate treatment response. The treatment was efficacious and met the partial response criteria after three treatment cycles, and the coughing and dyspnea resolved. The primary mass and lymph node metastases continued to shrink after five treatment cycles. Therefore, the present case report suggests that a combination of cadonilimab and anlotinib is a potential treatment strategy for patients with pulmonary LCNEC.