CD274 and cholangiocarcinoma: However, Yoon et al. investigated TIL solely by determining the CD8 + status by immunohistochemistry in a sub cohort of PD-L1-inhibitor treated patients in recurrent or unresectable CCA that underwent upfront chemotherapy, which likely affected the immune landscape (Yoon et al. 2021), while we used NanoString® technology in treatment naïve tumor tissue.