Primary myelofibrosis

Changed by Yuranga Weerakkody, 30 Apr 2022

Updates to Article Attributes

Body was changed:

Show markup changes

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

extramedullary ~~hematopoiesis~~haematopoiesis
progressive splenomegaly
anaemia
variable change in the number of granulocytes and platelets including thrombocytopenia

Epidemiology

It usually affects the middle-aged to elderly, with a mean age of 60 years⁶. The estimated prevalence is ~1:100,000. There may be a slight male predilection¹² .

Pathology

It a chronic clonal stem cell disorder and is considered a chronic BCR-ABL1 (breakpoint cluster region-Abelson murine ~~leukemia~~leukaemia viral oncogene homologue 1)-negative myeloproliferative disorder ¹¹.

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 ⁸.

Radiographic features

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

General

lymphadenopathy

Musculoskeletal

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

Abdominal

hepatomegaly
splenomegaly: can be massive
- some patients may also experience splenic infarcts ¹¹
evidence of portal hypertension ³
- from increased splenic blood flow
- from portal flow obstruction from the sinusoidal haematopoietic proliferation

Cardiovascular

may show evidence of congestive cardiac failure due to anaemia ³

Treatment and prognosis

Prognosis is poor, with slow progression and death usually within 2-3 years. It can also transform into acute myeloid leukaemia in a small number of patients ¹⁰.

Complications

gout: from hyperuricaemia due to increased haematopoietic turnover
complications with splenomegaly ¹²
- splenic infarction
- splanchnic vein thrombosis
- portal hypertension
- mass effect symptoms
- splenic rupture (rare) ⁹
bleeding from thrombocytopenia (see case 8)
thromboembolic events
- up to 10% of patients experience a thromboembolic event, most commonly venous thromboembolism

Differential diagnosis

General differential considerations include:

for musculoskeletal manifestations: consider the differential diagnosis of diffuse bony sclerosis
for splenic manifestations: consider differential diagnosis for splenomegaly

~~-<li><a href="/articles/extramedullary-haematopoiesis">extramedullary hematopoiesis</a></li>~~
+<li><a href="/articles/extramedullary-haematopoiesis">extramedullary haematopoiesis</a></li>
~~-<li>variable change in the number of granulocytes and platelets including thrombocytopenia</li>~~
-</ul><h4>Epidemiology</h4><p>It usually affects the middle-aged to elderly, with a mean age of 60 years<sup> 6</sup>. The estimated prevalence is ~1:100,000.</p><h4>Pathology</h4><p>It is considered a chronic BCR-ABL1 (breakpoint cluster region-Abelson murine leukemia viral oncogene homologue 1)-negative myeloproliferative disorder <sup>11</sup>.</p><p>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 <sup>8</sup>.</p><h4>Radiographic features</h4><p>Most radiological features are a result of extramedullary haematopoiesis and seen in many systems.</p><h5>General</h5><ul><li><a href="/articles/lymph-node-enlargement">lymphadenopathy</a></li></ul><h5>Musculoskeletal</h5><ul><li>
+<li>variable change in the number of granulocytes and platelets including <a title="thrombocytopenia" href="/articles/thrombocytopenia">thrombocytopenia</a>
+</li>
+</ul><h4>Epidemiology</h4><p>It usually affects the middle-aged to elderly, with a mean age of 60 years<sup> 6</sup>. The estimated prevalence is ~1:100,000. There may be a slight male predilection<sup>12</sup> .</p><h4>Pathology</h4><p>It a chronic clonal stem cell disorder and is considered a chronic BCR-ABL1 (breakpoint cluster region-Abelson murine leukaemia viral oncogene homologue 1)-negative myeloproliferative disorder <sup>11</sup>.</p><p>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 <sup>8</sup>.</p><h4>Radiographic features</h4><p>Most radiological features are a result of extramedullary haematopoiesis and seen in many systems.</p><h5>General</h5><ul><li><a href="/articles/lymph-node-enlargement">lymphadenopathy</a></li></ul><h5>Musculoskeletal</h5><ul><li>
+<li>complications with splenomegaly <sup>12</sup><ul>
+<li><a title="splenic infarction" href="/articles/splenic-infarction">splenic infarction</a></li>
+<li><a title="splanchnic vein thrombosis" href="/articles/splanchnic-vein-thrombosis">splanchnic vein thrombosis</a></li>
+<li><a title="portal hypertension" href="/articles/portal-hypertension">portal hypertension</a></li>
+<li>mass effect symptoms </li>
+</ul>
+</li>
+<li>thromboembolic events<ul><li>up to 10% of patients experience a thromboembolic event, most commonly venous thromboembolism </li></ul>
+</li>

References changed:

12. Oon S, Singh D, Tan T et al. Primary Myelofibrosis: Spectrum of Imaging Features and Disease-Related Complications. Insights Imaging. 2019;10(1):71. <a href="https://doi.org/10.1186/s13244-019-0758-y">doi:10.1186/s13244-019-0758-y</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/31388788">Pubmed</a>

ADVERTISEMENT: Supporters see fewer/no ads

{"current_user":null,"inclusions":[{"imageId":573925,"studyId":12013,"caseSlug":"myelofibrosis-1","caption":"Case 1: with widespread decreased marrow signal","thumbnail":"https://prod-images-static.radiopaedia.org/images/573925/04c5d759d170578c07d2bcd14415ec_big_gallery.jpg","isStack":false,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":573903,"studyId":12012,"caseSlug":"myelofibrosis","caption":"Case 2","thumbnail":"https://prod-images-static.radiopaedia.org/images/573903/44d6157942d34e69d62d3d105c8c9e625e340c6a9001cc975d1880697e700a35_big_gallery.jpeg","isStack":false,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":573891,"studyId":49088,"caseSlug":"myelofibrosis","caption":"Case 2","thumbnail":"https://prod-images-static.radiopaedia.org/images/573891/d0dd919e51a77912fd0241e05ceac5_big_gallery.jpg","isStack":false,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":2348899,"studyId":19477,"caseSlug":"myelofibrosis-2","caption":"Case 3","thumbnail":"https://prod-images-static.radiopaedia.org/images/2348899/8fef800f7e7d682a28f130069a7433_big_gallery.jpg","isStack":true,"diagnosticCertainty":"probable"},{"imageId":3466095,"studyId":23233,"caseSlug":"myelofibrosis-3","caption":"Case 4 ","thumbnail":"https://prod-images-static.radiopaedia.org/images/3466095/b9242152c6cc3537dcc749f319702a6121a81720a5a8370d2a7f090bbd59bed5_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":6705517,"studyId":29165,"caseSlug":"myelofibrosis-4","caption":"Case 5","thumbnail":"https://prod-images-static.radiopaedia.org/images/6705517/8c98f44853dec46a80896f9c3b9f29_big_gallery.jpg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":8641732,"studyId":32334,"caseSlug":"splenic-infarction-9","caption":"Case 6: with hepatosplenomegaly","thumbnail":"https://prod-images-static.radiopaedia.org/images/8641732/037bb3e9e5d26f79f03059ad06bf1b_big_gallery.jpg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":30361958,"studyId":59358,"caseSlug":"myelofibrosis-massive-splenomegaly-with-infarct-1","caption":"Case 7: myelofibrosis with massive splenomegaly and infarct","thumbnail":"https://prod-images-static.radiopaedia.org/images/30361958/57133d24bb6e28012abb21e4c0a601_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":29730177,"studyId":58494,"caseSlug":"acute-subdural-haematoma-with-myelofibrosis","caption":"Case 8: acute SDH with myelofibrosis","thumbnail":"https://prod-images-static.radiopaedia.org/images/29730177/805d71eb061d4c401e2c68d7ddcd38cdf6ed5b6a10b7e7f7ba6f2264619b1411_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":52111395,"studyId":85670,"caseSlug":"myelofibrosis-8","caption":"Case 9","thumbnail":"https://prod-images-static.radiopaedia.org/images/52111395/a5d2d8bf2fe82d0f78f1ef7398bc89_big_gallery.jpeg","isStack":false,"diagnosticCertainty":"confirmed_substantiated"},{"imageId":54055750,"studyId":100584,"caseSlug":"myelofibrosis-9","caption":"Case 10","thumbnail":"https://prod-images-static.radiopaedia.org/images/54055750/IMG-0003-00036_big_gallery.jpeg","isStack":true,"diagnosticCertainty":"confirmed_unsubstantiated"},{"imageId":65404991,"studyId":148635,"caseSlug":"myelofibrosis-12","caption":"Case 11","thumbnail":"https://prod-images-static.radiopaedia.org/images/65404991/a43ab9ae2b3e5b1e1f3e03dcdf2916ae2f1953a15994358498753c8412ab3bef_big_gallery.jpeg","isStack":false,"diagnosticCertainty":"confirmed_unsubstantiated"}],"ddx_inclusions":[],"lang":"us"}