CD274 and neoplasm: Of note, sarcomatoid MPM (n = 2), a histological subtype that has more mesenchymal stromal compartments and predicts poorer prognosis 34, has higher basal expression of PD-L1, and chemotherapy induced PD-L1 upregulation in one sarcomatoid tumor with lower basal PD-L1 expression (Figure 3B).