Myelosclerosis

Primary myelofibrosis is a myeloproliferative neoplasm in which there is the replacement of bone marrow with collagenous connective tissue and progressive fibrosis. It is characterized by:

Epidemiology

It usually affects the middle-aged to elderly, with a mean age of 60 years. The estimated prevalence is ~1:100,000.

Pathology

It is considered a chronic BCR-ABL1 (breakpoint cluster region-Abelson murine leukemia viral oncogene homologue 1)-negative myeloproliferative disorder .

Non-neoplastic fibroblasts produce collagen, which replaces normal bone marrow elements. This bone marrow fibrosis is a result of an inappropriate release of PDGF and TGF-ß from neoplastic megakaryocytes .​

Radiographic features

Most radiological features are a result of extramedullary hematopoiesis and seen in many systems.

General
Musculoskeletal
  • osteosclerosis
    • diffuse pattern
    • no bony architectural distortion
    • typical distribution:
      • axial skeleton
      • ribs
      • proximal humerus and femur
    • bone scan may give "superscan" appearance
Abdominal
Cardiovascular

Treatment and prognosis

Prognosis is poor, with slow progression and death usually within 2-3 years. It can also transform into acute myeloid leukemia in a small number of patients .

Complications
  • gout: from hyperuricemia due to increased hematopoietic turnover
  • splenic rupture (rare)
  • bleeding from thrombocytopenia (see case 8)

Differential diagnosis

General differential considerations include:

See also

Siehe auch:
und weiter: