CD274 and neoplasm: In the whole case series, 7 (10%) glioblastomas showed “high” (staining in ≥50% of tumor cells) PD-L1 expression, and 21 (31%) showed intermediate (staining in 1% to 50% of tumor cells) expression, for a total rate of PD-L1-positive cases of 41% (Figure 3a).