Publication

Abstract : Accelerated and abnormal angiogenesis is an integral feature of the myeloproliferative neoplasms (MPN).1 Of all MPN, primary myelofibrosis (PMF) displays the highest angiogenesis.2 This forms the rationale behind the use of anti-angiogenesis agents in patients with PMF.3 Bone marrow fibrosis (MF) also occurs secondarily in many hematologic and nonhematologic disorders. A few studies indicate that these fibrosing disorders too are associated with enhanced angiogenesis.4,5 However, to the best of our knowledge, no direct quantitative comparison of angiogenesis in conditions with secondary MF vs. the MPN, including PMF, exists in indexed Englishlanguage literature. Such a comparison is of potential diagnostic utility since morphologic distinction between PMF and secondary MF can be challenging. Even with the advent of molecular markers, ~40–50% of patients with PMF are negative for both JAK2 and cMPL mutations and current diagnostic criteria require exclusion of any secondary causes of MF.6,8 In addition, increased vascular density is one of the early events in the pathogenesis of PMF2, and comparisons with other disorders displaying marrow fibrosis might yield insights on the pathogenetic relationships and differences between the two groups. The present study utilized morphometry to quantitate immunohistochemically highlighted angiogenesis in proven cases of PMF and secondary MF resulting from various causes, with a view to explore its potential use in differentiating PMF from secondary MF.