Myeloproliferative neoplasms in Mexico: An analysis of clinical features, driver mutations, and disease progression patterns in a case series.

Abstract Myeloproliferative neoplasms (MPNs) are chronic hematologic malignancies characterized by clonal myeloid proliferation, risking progression and thrombohemorrhagic complications. While global understanding of MPNs, including Polycythemia Vera (PV), Essential Thrombocythemia (ET), and primary myelofibrosis (PMF), is growing, specific data on their prevalence and characteristics in the Mexican population remain limited. This retrospective case series aimed to address this gap by analyzing 63 adult patients (PV n=27, ET n=20, MF n=16) diagnosed per WHO criteria from Pensiones Civiles del Estado de Chihuahua, Hospital Central del Estado de Chihuahua y Hospital Angeles Chihuahua, between 2018 and 2025. We extracted demographic data (age, sex, age at diagnosis), reported mutations (JAK2, CALR, MPL, triple-negative status), treatments, disease progression, thrombosis prevalence, and mortality. Descriptive statistics, Chi-square/Fisher tests, and ANOVA/Kruskal-Wallis tests were employed. Our findings revealed a mean age at diagnosis of 59.9 years for the cohort, with ET showing female predominance (60.0%) and PV (53.8%) and MF (62.5%) male predominance. The JAK2 V617F mutation was most frequent in ET (50.0%) and MF (56.25%), while triple-negative status was observed in 15.0% of ET and 25.0% of MF patients. A striking finding was the high prevalence of thrombosis: 25.0% in ET, 38.5% in PV, and a notable 50.0% in MF. Disease progression was also significant, affecting 30.0% of ET patients (71.4% to PV, 28.6% to MF) and 15.4% of PV patients (originating from ET). Mortality was higher in MF (8 deaths) and PV (6 deaths), with no deaths recorded in ET. These results present notable discrepancies with international literature: the observed thrombosis prevalence in MF (50.0%) and ET (25.0%) is considerably higher than reported incidence rates (e.g., 1.75-2.2% patient-years in MF and 1-3% patient-years in ET ), suggesting a greater thrombotic burden in our population. Furthermore, ET progression rates (30.0% overall) exceed published figures (4.3% for ET to MF, 6.7% for PV to MF ), and the progression of ET to PV is an atypical finding, potentially indicating a more aggressive disease evolution or delayed diagnosis. The proportion of triple-negative MF patients (25.0%) is also slightly higher than typical ranges (10-15% ). In conclusion, this mexican series reveals a higher burden of thrombotic complications and disease progression than expected from international data. These findings underscore the critical need for intensified surveillance and personalized management strategies for MPN patients, particularly in diverse geographic and ethnic contexts.