PB2229 DISEASE CHARACTERISTICS AND RESPONSE TO TREATMENT OF PATIENTS WITH MYELOFIBROSIS:A MULTICENTRE DESCRIPTIVE, RETROSPECTIVE STUDY FROM SRI LANKA
Authors: D. Moratuwagama, Y. Costa, S. Senanayake, H. Williams, B. Jayaratne B, V. Rathnamalala, N. Ranasinghe, L. Gooneratne, H. Goonesekara, D. Gunewardena, I. Wijesiriwardene, C. Kulathilake C, A. Jayawardene A, J. D. Silva, I. Dharmasena, N. Perera, N. Mendis, P. Vitharana, R. Jayathunga, H. Gunasekara, L. Basnayake, Y. Samaraweera, T. Sooriyakumar, D. Dissanayake, W. Vidyaratne, K. Jayaratne, H. Alwis, R. Wijeratne, A. Attanayake, S. Athawuda, R. Pullaperuma, B. Somarathna, S. Yoganathan, L. Senerath, V. Gunawardena, B. Balasooriya, D. Epa, B. Fernandopulle, C. Moonesinhge
Journal: HemaSphere (2019)

Background: Myelofibrosis (MF)is a BCR/ABL negative, myeloproliferative neoplasm. The manifestations of MF include constitutional symptoms, splenomegaly, anaemia and other cytopenias. Most of the patients are elderly with multiple comorbidities and cannot undergo, allogeneic stem cell transplantation. Hence treatment is mainly aimed at controlling symptoms and complications. Given the varying clinical needs of these patients, and the wide array of therapeutic options available, it is challenging to choose the best therapeutic agents for each patient. Aims: The main objective of this multicenter study, the first of this nature for MF in Sri Lanka, was to describe clinical and laboratory characteristics of patients and to assess various treatment modalities practiced. Methods: Following informed written consent, data was gathered from 28 units covering all provinces in the country. Analysis was using SPSS software. Results: Of the 104 patients with MF 87 were primary,16 post polycythemia vera and one post essential thrombocythemia. Median age 58.9years, male:female ratio 51:49.The main presenting features were splenomegaly 78.8%,constitutional symptoms 63.5% and anemia 59.6%. Leukocyte count >25x109/L, blasts in the peripheral blood and platelets <100x109/L were seen in 23.1%,18.3 and 17.3%.JAK 2 V617Fmutation was checked only in 77patients due to lack of facilities and 61% were positive. 62 paitents were anemic and required frequent or intermittent transfusions. 32 patients received Erythropoietin,19 Thalidomide/ Prednisolone and 7 Thalidomide only. Positive responses were seen in 53.1%, 52.6% and 42.9% respectively. Splenomegaly was seen in 82 patients.70 received Hydroxyurea,13Ruxolitinib, 10Thalidomide/ Prednisolone and 10 Thalidomide only. Positive responses were seen in 77.1%,61.5%, 50% and 50% respectively. Constitutional symptoms were treated with Ruxolitinib in 14 patients. 92.9% showed a positive improvement. The presenting clinical and laboratory features of our patients were compared with similar studies by Cervantes et al., 2009 on 1054 patients from Europe and north America and ZefengXu et al., 2011on 642 Chinese patients. Our cohort had statistically higher number of patients with constitutional symptoms, anemia and high leukocyte count but surprisingly statistically lower number of patients with blasts in the peripheral blood as compared to the Caucasians. The Chinese patients had statistically lower mean age and constitutional symptoms but higher number of patients with thrombocytopenia. Summary/Conclusion: Statistically significant differences in clinical and laboratory features at presentation were seen between Sri Lankan patients and the Caucasians/the Chinese. This highlights varying manifestations of MF in different races and should be considered when formulating prognosticating scoring systems. Hydroxyurea remains the most effective, commonly used and the least expensive treatment option for splenomegaly. Thalidomide/Prednisolone and Thalidomide alone have similar positive responses when used against anemia and splenomegaly but the patient number is small and should be further analysed with a larger study population. JAK inhibitor, Ruxolitinib though used only in14patients has shown a good response in controlling constitutional symptoms and splenomegaly, but the use of the drug was limited by high cost and anaemia.