Molecular, Clinical, and Hematological Characteristics of Myeloproliferative Neoplasms in Yemen: A Prospective Cross- Sectional Study

Purpose Myeloproliferative neoplasms (MPNs) are clonal hematopoietic disorders whose diagnosis relies on integrating clinical, morphological, and molecular data. Comprehensive data on the molecular landscape of MPNs from resource-limited regions like Yemen are scarce. This study aimed to characterize the molecular, clinical, and hematological profile of MPN patients in Yemen. Methods A prospective cross-sectional study was conducted on 118 patients with suspected MPNs at Al-Thawra Modern General Hospital, Sana’a, from August 2024 to May 2025. Diagnosis was established using WHO 2016 criteria, incorporating peripheral blood film, bone marrow evaluation, and molecular analysis for BCR-ABL1 , JAK2 V617F, CALR , and MPL mutations. Results Of 100 patients initially suspected of CML, 94 were BCR-ABL1 -positive. The remaining 6 were reclassified after further testing. The final cohort of 118 MPN patients included 94 (79.7%) CML, 21 (17.8%) Ph-negative MPNs (6 PV, 10 PMF, 5 ET), and 3 (2.5%) other rare MPNs. The median age was 41.5 years, with a male-to-female ratio of 1.4:1. CML patients were significantly younger than Ph-negative MPN patients (median age 38.5 vs. 56.0 years, p < 0.001). Among the 21 Ph-negative MPNs, a driver mutation was identified in 19 cases (90.5%): JAK2 V617F was most frequent (12/21, 57.1%), followed by CALR (6/21, 28.6%), and MPL (1/21, 4.8%). Two cases (9.5%) were triple-negative. Conclusion This study provides the first prospective data on the comprehensive molecular landscape of MPNs in Yemen. It confirms the high frequency of driver mutations and demonstrates the indispensable role of a full molecular panel for accurate classification of MPNs, highlighting the critical need to integrate these diagnostics into the standard of care in resource-limited settings.