Background: Hepatotoxicity is a well-recognised side effect of tyrosine kinase inhibitors (TKI) and in some patients it can be a challenge to find a well-tolerated and effective drug. Isolated hyperbilirubinemia is common but, particularly in the case of nilotinib, is generally attributed to concomitant Gilbert's syndrome, characterized by the reduced expression of uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1). We have previously reported hyperbilirubinemia in association with the homozygous Gilbert genotype in patients treated with imatinib, dasatinib and nilotinib and have now extended our studies to more recent TKI. In addition we have analysed the incidence of TKI-associated transaminitis and attempted to identify safer alternative TKI.