The reality of cancer treatment in a developing country: the effects of delayed TKI treatment on survival, cytogenetic and molecular responses in chronic myeloid leukaemia patients

Summary Cancer patients in developing and low‐income countries have limited access to target therapies. For example, tyrosine kinase inhibitor (TKI) therapy for chronic myeloid leukaemia patients (CML) is often delayed. In Bosnia, 16% of patients received immediate TKI treatment (13 months delay). The primary endpoints were complete cytogenetic (CCyR) and major molecular response (MMR) at 12 months. At 12 months of therapy, CCyR and MMR rates on imatinib decreased significantly: CCyR was achieved in 67% of patients in the immediate imatinib treatment group, 18% of patients in 6–12 months group and 15% of patients in >13 months wait group. MMR rates at 12 months occurred in 10% of patients with immediate treatment, 6% of those in 6–12 months group and 0% of patients in >13 months wait group. However, CCyR and MMR rates in patients on nilotinib were not associated with duration of treatment delay. Our data suggests that the deleterious effect of a prolonged TKI therapy delay may be ameliorated by the more active TKI nilotinib.