CD274 and solitary fibrous tumor: The phase II PEMBROSARC trial of pembrolizumab with cyclophosphamide in 50 patients with locally advanced or metastatic sarcomas (both treatment-naive and pretreated patients), including LMS, UPS and GIST, showed limited activity, with just one PR in a patient with solitary fibrous tumor (SFT) with PD-L1 expression greater than 10% in immune cells [56].