Myeloproliferative neoplasms: is the vascular network a prognostic feature?

Abstract

Myeloproliferative neoplasms are a group of disorders that comes from the clonal proliferation of hematopoietic precursor cells, resulting in an increased number of myeloid series in blood. These entities, though infrequent, have clinical consequences in common and can also cause bone marrow fibrosis. They also show increased levels of angiogenesis and a different morphometric standard. This association is well established nowadays, although its relation with clinical evolutive characteristics might be better studied. Therefore is believed this association might be a new parameter to make the diagnosis and to determine the prognosis of these entities. The project intends to analyse the microvessel density inside the bone marrow of people who have Polycythemia Vera (PV), Essential Thrombocythemia (ET) and Primary Myelofibrosis (PMF) and to compare it with clinical and evolutive data of these patients. A group of 63 patients will be studied, 21 with PV, 25 with TE, and 17 with MF. There will be a control group of 50 patients, whose biopsies come from the negative staging of neoplastic infiltration of bone marrow. The methods consist in morphological analysis of histological blades stained with Hematoxylin, Perls and reticulin techniques, and also in immunohistochemical analysis of these blades, using CD34, CD105, Factor VIII and VEGF markers, being the last one important to evaluate the intensity and extension of its stain in endothelial cells.