The outcome of allo-HSCT for 92 patients with myelofibrosis in the Nordic countries.

Between 1982 and 2009 a total of 92 patients with myelofibrosis (MF) in chronic phase underwent allo-SCT in nine Nordic transplant centers. Myeloablative conditioning (MAC) was given to 40 patients, and reduced intensity conditioning (RIC) was used in 52 patients. The mean age in the two groups at transplantation was 46±12 and 55±8 years, respectively (P<0.001). When adjustment for age differences was made, the survival of the patients treated with RIC was significantly better (P=0.003). Among the RIC patients, the survival was significantly (P=0.003) better for the patients with age <60 years (a 10-year survival close to 80%) than for the older patients. The type of stem cell donor did not significantly affect the survival. No significant difference was found in TRM at 100 days between the MAC- and the RIC-treated patients. The probability of survival at 5 years was 49% for the MAC-treated patients and 59% in the RIC group (P=0.125). Patients treated with RIC experienced significantly less aGVHD compared with patients treated with MAC (P<0.001). The OS at 5 years was 70, 59 and 41% for patients with Lille score 0, 1 and 2, respectively (P=0.038, when age adjustment was made). Twenty-one percent of the patients in the RIC group were given donor lymphocyte infusion because of incomplete donor chimerism, compared with none of the MAC-treated patients (P<0.002). Nine percent of the patients needed a second transplant because of graft failure, progressive disease or transformation to AML, with no significant difference between the groups. Our conclusions are (1) allo-SCT performed with RIC gives a better survival compared with MAC. (2) age over 60 years is strongly related to a worse outcome and (3) patients with higher Lille score had a shorter survival.