Laboratories are likely to adopt CPATH once they know which algorithm to choose for a given question (e.g., to diagnose a specific pathology or interpret a particular marker) and this is of relevance to a sufficient number of pathologies/markers to make it practical (e.g., programmed cell death ligand 1 [PD-L1] across tumour types with HER2/ER/PR in the breast plus Ki67 and counting of mitoses across tumour types). This evidence concerns the gene PGR and neoplasm.