In a recent multi-center prospective study of 173 patients with CML-CP receiving treatment with imatinib, dasatinib, nilotinib, or bosutinib, treatment was discontinued after documentation of continuous DMR for at least 2 years [6]; after a median follow-up of 41.6 months from time of treatment discontinuation, 65.5% stayed in MMR and the likelihood of molecular recurrence was lowest in the absence of detectable BCR::ABL1 at time of treatment discontinuation [6]. This evidence concerns the gene BCR and chronic myelogenous leukemia, BCR-ABL1 positive.