Allogeneic stem cell transplantation (SCT) in Ph+ CML: still a therapeutic option?
Allogeneic stem cell transplantation (SCT) is the only curative treatment in Philadelphia positive chronic myeloid leukaemia. Because of the good results of Imatinib and the toxicity of transplantation SCT has lost its place in first line treatment of CML. In the last decade a new modality of SCT (with reduced intensity conditioning = RIC-SCT) was used to lower treatment mortality (TRM) of SCT and to transplant also elderly patients (over 50 years), even with comorbidities. A.Gratwohl published a risk score for SCT (EBMT score) to categorize patients with low, intermediate and high TRM. An useful tool is also the comorbidity index (HCT-CI) of Sorror to define patients for different transplant procedures (standard SCT vs. RIC-SCT). Stem cell transplantation is indicated in CML patients, who have no adequate response to Imatinib or second tyrosine kinase inhibitors (TKI), in patients after accelerated phases or blastic crisis and in patients (with low EBMT score) with mutations, which predict a failure to TKI therapy. For these patients a projected 5-year survival range between 50 and 70%.