CD274 and neoplasm: Hayano et al. reported that patients with tumor cells expressing PD-L1 had a significantly longer survival time than patients with tumor cells not expressing PD-L1 [4]; however, there was no significant correlation between the survival time and the PD-L1 expression on tumor stromal cells, although there was a trend for the tumors with PD-L1-negative stromal cells to have longer survival times compared to the tumors with PD-L1-positive stromal cells.