Bridging the diagnostic gap in myeloproliferative neoplasms

previously reported the successful implementation of molecular testing for classical myeloproliferative neoplasms (MPNs) within a resource-constrained Brazilian public health care system (HCS), demonstrating that precision diagnostics can be both feasible and sustainable beyond highincome settings.The discovery of recurrent driver mutations in JAK2, CALR, and MPL fundamentally transformed the diagnosis of Philadelphia chromosome-negative MPNs. 2 Molecular testing now anchors international diagnostic algorithms, confirming clonality, supporting disease classification, and increasingly informing prognosis and therapeutic decisions.3 Although molecular diagnostics have rapidly become standard practice in high-income countries, access remains heterogeneous across much of the world.4 For many HCSs, the challenge is no longer whether molecular testing is clinically valuable but how it can be effectively implemented within the existing clinical and laboratory infrastructure.In this issue of Blood Global Hematology, Coelho-Silva et al described their 20-year experience with the molecular diagnosis of classical MPNs at a large public referral center in Pernambuco, in a part of Brazil marked by pronounced regional disparities in health care infrastructure and among the country's lowest levels of socioeconomic development.Their study characterized the molecular landscape and clinical outcomes of >450 patients and demonstrated that routine testing for the 3 canonical driver mutations can be successfully integrated into a resource-constrained public HCS.Given the limited representation of low-and middle-income countries (LMICs) in the MPN literature, this experience provides valuable insight into the realities of delivering modern hematologic care outside highly specialized academic centers.Although the mutation frequencies reported here are informative, this study's broader contribution lies in highlighting a challenge that extends across modern hematology: implementation science.5 Developing effective diagnostic molecular technologies is only the first step toward precision medicine.Ensuring that these technologies can be sustainably integrated into diverse HCSs represents an equally important, and often more difficult, challenge.6 Precision medicine cannot achieve its full potential without precision implementation.