Intensive chemotherapy in patients with chronic myelogenous leukaemia (CML) in accelerated or blastic phase – a report from the Swedish CML Group

In attempting to restore the chronic phase (CP) of chronic myelogenous leukaemia (CML), the Swedish CML group utilized an intensive chemotherapy protocol for 83 patients (aged 16-79 years) in accelerated (AP, n = 22) or blastic phase (BC, n = 61). Most patients received a combination of mitoxantrone (12 mg/m(2) /d) and etoposide (100 mg/m(2) /d) together with cytosine arabinoside (1 g/m(2) b.i.d) for 4 d. Overall, 39 patients (47%) achieved a second CP (CP2)/partial remission (PR). Responding patients < 65 years were eligible for ablative chemotherapy followed by an allogeneic (SCT) or a double autologous stem cell transplant (ASCT). Seventeen of 34 responders < 65 years failed to proceed to transplantation as a result of early disease progression (n = 15) or disease-related complications (n = 2). The remaining 17 patients underwent SCT (n = 9; including four unrelated donor SCT) or ASCT (n = 8). Only one of the eight ASCT patients had a second ASCT; the remaining seven failed because of progression (n = 5) or hypoplasia (n = 2). The median duration of CP2/PR was 6 months (range 1-72 months). Five patients achieved a longer CP2/PR than CP1. The 1 year survival was 70% for SCT/ASCT patients (median survival 21 months), 50% for responding patients overall, but only 7% for non-responders (P < 0.001). Three SCT/ASCT patients are long-term survivors (65+, 66+ and 73+ months). In conclusion, approximately half of the patients achieved a CP2/PR after intensive chemotherapy, with a clear survival advantage for responders vs non-responders. Subsequent SCT/ASCT was feasible for half of the responders (< 65 years), and one individual underwent double ASCT. Novel therapeutic options for CML patients in AP/BP are needed.