Allogeneic Hematopoietic Cell Transplants in Patients with Myelofibrosis Age 60 and Older

Allogeneic Hematopoietic Cell Transplants in Patients with Myelofibrosis ≥ 60 years of age. Primary myelofibrosis (PMF) and myelofibrosis arising from polycythemia vera (PV) and essential thrombocythemia (ET) are challenging clinical entities and many patients have a very poor prognosis. For the most part, treatment is palliative and often of limited efficacy. Allogeneic hematopoietic cell transplants (HCT) can effectively control the disease, and reduced intensity conditioning regimens have reduced regimen related complications. However, many studies have excluded patients older than age 65 (or even 60) years. This is problematic as the median age at diagnosis is approximately 67. We retrospectively evaluated a cohort of 26 patients age ≥ 60 years with PMF or post PV or ET myelofibrosis who underwent allogeneic HCT between 1999 and 2007. The median age was 63 (range 60–75) years; 9 of these patients were older than 65 (range 66–75) years. Donors were HLA-matched siblings (n=14) or unrelated (n=12). Conditioning regimens included Fludarabine (Flu)/2 Gy TBI (n=16), Flu/Campath(Cam)/TBI (n=2), Flu/Melphalan/ATG (n=2), Cam/Flu/CD45Mab/4.5 Gy TBI (n=2), Flu/Busulfan (Bu) (n=2), Flu/Bu/ATG (n=1), Flu/Mel/Cam (n=1). The median follow up for the cohort was 200 (range 17 – 1322) days. Eleven of 26 patients were alive at the date of last followup, and 9 were relapse free. The median follow up for living patients was 251 (range 100 – 1322) days. Of the 15 patients who had died, 5 died of disease progression and the remaining 10 of non-relapse causes: infection (n=4), GVHD (n=2), respiratory failure (n=2), multi-organ failure (n=1), dissecting aneurysm (n=1). At last follow up, 4 of 9 patients age >65 were alive a median of 374 (range 132 – 896) days without disease relapse. Five of the nine patients died, 4 from non-relapse causes and one with disease progression. In summary, reduced intensity conditioning and allogeneic transplantation in patients with myelofibrosis more than 60 years of age resulted in relapse-free survival of 40–45%. While the mortality rate was high, the success rate was remarkable in view of the patient age and the frequent presence of co-morbid conditions. We suggest, therefore, that ongoing and future clinical trials of allogeneic HCT for myelofibrosis should allow enrollment of older patients.