Numbers of pan-T cell infiltrations (CD3+ cells) and macrophages (CD68+ cells) of TKI-naive GISTs were comparable to those in a previous report.15 Although another previous study presented that tumour PD-L1 expression (29%) and lymphocyte PD-L1 expression (50%) were relatively common in GISTs,12 our study showed that cytotoxic T cells (CD8+ CD3+), T cells with exhausted phenotype (regulatory T cells [FoxP3+ CD3+], PD-L1+ T cells, and TIM-3+ T cells) were scarce in TKI-naive GISTs. Here, CD274 is linked to neoplasm.