A 42-year-old male...showed a high-grade myxofibrosarcoma...About 40% to 50% of tumor cells in his pulmonary tissues were showed positive PD-L1 expression and his tumor mutational burden was 215Muts....Then the patient received 3 cycles of chemotherapy with cisplatin, ifosfamide and epirubicin....a follow-up chest computed tomography (CT) scan (July 1, 2018) depicted enlarged nodules, indicating disease progression...myxofibrosarcoma with no response to conventional therapeutic options, immunotherapy is a promising selection.