Discontinuation of imatinib therapy after achievement of complete molecular response in a Ph+ CML patient treated while in long lasting complete cytogenetic remission (CCR) induced by interferon.

Imatinib has become the gold standard therapy for Ph(+) CML, as it induces complete cytogenetic remission (CCR) in 75-90% of patients in chronic phase (CP), and up to 40% of these patients obtain at least a 3 log reduction of BCR/ABL transcript [Kantarjian HM, Cortes JE, O'Brien S, Luthra R, Giles F, Verstovsek S, et al. Long-term survival benefit and improved complete cytogenetic and molecular response rates with imatinib mesylate in Philadelphia chromosome-positive chronic-phase chronic myeloid leukemia after failure of interferon-alpha. Blood. 2004;104:1979-1988]. However, it is not yet stated whether continued therapy is required to maintain this response or whether imatinib may be discontinued after confirmation of a prolonged complete molecular remission (CMR). We here report on a Ph(+) CML case in long lasting CCR following interferon-alpha treatment (IFN) which reached CMR with imatinib but soon relapsed at molecular level after this latter drug discontinuation; we considered the present observation also in the light of previously reported data.