Survival probability. (A) After allo-SCT. Patients with elective transplantation in first CP (n = 20; group I) and patients who underwent transplantation after imatinib failure in first CP (n = 36; group II) had a 3-year survival probability of 88% and 94% (CI: 69.3-98.7 and 83.9-99.4), respectively; patients who underwent transplantation in advanced disease (n = 28; group III) had a 3-year survival probability of 59% (CI: 38.6-77.5). Tick marks indicate last observation of living patients. (B) Matched pair analysis. For each of 53 patients who underwent transplantation, 2 matched imatinib-treated patients (n = 106 in total) were found who were in first CP at the time of transplantation of the matched partner. Observation intervals of patients who did not undergo transplantation were appropriately matched with those who did for the time between diagnosis and transplantation. A patient who underwent transplantation in first chronic phase on day X has a guaranteed survival time from diagnosis to day X. To ensure a fair comparison, the 2 matched imatinib-treated partners had to have survived and been in first chronic phase on day X, too. Survival probabilities showed no difference. Tick marks indicate last observation of living patients.