Significant benefit of Nivolumab treating PD-L1 positive metastatic pulmonary carcinosarcoma: a case report and literature review

Immunotherapy has recently become a new focus for the treatment of malignant tumors following the surgery, chemotherapy, radiotherapy, and molecular targeted therapy. Nivolumab, a human monoclonal antibody, is the first programmed cell death protein-1 (PD-1) inhibitor, which can prohibit the interaction of its ligand (PD-L1), restoring the immune response of T cells, and enhancing the recognition of tumor cells by the immune system. Pulmonary carcinosarcoma is an uncommon but highly aggressive tumor type with a poor prognosis. We described a case of pulmonary carcinosarcoma, with the positive expression of PD-L1, obtained a significant benefit from Nivolumab treatment in a 64-year-old Chinese man, which give us a clue that patients with pulmonary carcinosarcoma may benefit fromanti-PD-1 immunotherapy.