Myeloproliferative neoplasms
Introduction
A group of clonal disorders of the hematopoietic stem cells,
which are characterised by proliferation of one or more hematopoietic lineages.
Maturation is relatively normal — effective hematopoiesis.
Clinical signs
- predominantly elderly people (50 – 60 years of age)
- incidence 6 – 9/100.000
- polyglobulia
- leukocytosis
- thrombocytosis
- organomegaly
Classification
WHO classifies MPNs into tho categories according to the presence of the BCR/ABL1 fusion gene:
- BCR/ABL1 positive:
- chronic myeloid leukemia (CML)
- BCR/ABL1 negative:
- polycythemia vera (PV)
- essential thrombocythemia (ET)
- primary myelofibrosis (PMF)
- chronic neutrophilic leukemia (CNL)
- chronic eosinophilic leukemia (CEL)
- mastocytosis
- MPN unclassifiable (MPN-U)
Grades of bone marrow fibrosis in myeloproliferative neoplasms:
- MF-0: scattered linear reticulin with no intersections
- MF-1: loose network of reticulin with many intersections,
especially in perivascular areas
- MF-2: Diffuse and dense reticulin network with extensive
intersections, occasionally with focal bundles of
collagen or focal osteosclerosis
- MF-3: Diffuse dense reticulin network with extensive
intersections and coarse bundles of collagen, often
associated with significant osteosclerosis
