CD274 and metastatic malignant neoplasm in the lymph nodes: In conclusion, increased immune cell infiltration of T and B cells as well as higher levels of PD-L1 expression in AciCCs in association with high-grade transformation, lymph node metastasis and unfavourable prognosis suggests a relevant interaction between tumour cells and immune cell infiltrates and warrants further exploration of the efficacy of immunotherapies in clinical studies with inclusion of high grade AciCCs only.