The characteristics and treatment of patients with primary myelofibrosis at the University medical centre Ljubljana in the period 2008–2012

Abstract

Background: Primary myelofibrosis (PMF) is a rare hematologic condition belonging to the group of classical myeloproliferative neoplasms. For the diagnosis of PMF, bone marrow histology examination and fibrosis evaluation is mandatory. No recurrent cytogenetic abnormality has been identified and JAK2 mutation is present only in approximately half of the patients. Treatment is limited mainly to alleviation of B symptoms, splenomegaly and anemia. Only allogeneic hematopoietic stem-cell transplant (HSCT) can offer a cure from the disease. A new drug, JAK2 inhibitor ruxolitinib, that has been available since recently, will change treatment options mainly for patients not eligible for HSCT. Methods: Hipokrat medical database was searched for patients diagnosed with PMF between 2008–2012. Data were collected retrospectively and analysed using basic statistics. Results: PMF was newly diagnosed in 28 patients (18/64.3 % men). Two (7.1 %) patients presented with systemic symptoms and ten (35.7 %) had enlarged spleen. Their median blood counts and lactate dehydrogenase activity (LDH) results were: leukocytes 11.25 x 109/l (3.00–72.00), hemoglobin 117 g/l (68–173), platelets 420 x 109/l (111–1477), LDH 7.45 μkat/l (3.00–20.71). In six (21.4 %) patients only bone marrow cytology examination was performed without histologic examination. Cytogenetics was performed in 11 (39.3 %) patients with three abnormalities detected: complex, +9 and del(13q14). JAK 2 mutation was identified in 12 (60.0 %) of 20 examined cases. Patients were treated with acetylsalicylic acid (n = 12/42.9 %), hydroxyurea (n = 12/42.9 %), blood transfusions or epoetins (n = 12), anagrelide (n = 4/14.3 %), methylprednisolone (n = 4/14.3 %), immunomodulatory drugs (n = 3/10.7 %), interferon (n = 2/7.1 %), spleen irradiation (n = 2/7.1 %) and venipunctures (n = 2/7.1 %). At the end of 2011, first eligible patients were treated with ruxolitinib. Conclusions: PMF is a rare disorder with various presentations and treatment suited specifically to patients’ complaints. The treatment is symptomatic with HSCT being the only curable option available. Ruxolitinib will play an importatnt role in PMF treatment in the future.