Clusters 3 and 4 comprised mostly fluke-negative tumours: cluster 3 exhibited an upregulation of immune checkpoint genes (PD-1, PD-L2, and BTLA) and pathways related to antigen cross-presentation, CD28 co-stimulation, and T-cell signal transduction; cluster 4 was characterized by BAP1, IDH1/2 mutations, FGFR alterations and PI3K pathway signatures. The gene discussed is IDH1; the disease is neoplasm.