[Correspondence] How molecularly similar are primary and metastatic tissues in renal cell carcinoma?

We read the BIONIKK study by Yann-Alexandre Vano and colleagues.1 Improved survival was achieved with immunotherapies and tyrosine-kinase inhibitors in metastatic clear-cell renal cell carcinoma. This study showed that treatment choice, according to the molecular subtype, is feasible. However, we have a few concerns about the methods used in the study.