Discussion
Diagnosis With Brief Discussion
- Diagnosis
- Extramedullary hematopoiesis
- Radiologic Findings
- Fig 1-3. Contrast-enhanced CT scans show three uniformly enhancing paraspinal masses with no bony erosion.
- Brief Review
- This patient had anemia and splenomegaly.
On surgical specimen, the mass reveals extramedullary hematopoiesis.
The most common manifestation of extramedullary hematopoiesis (EMH) in the chest is paraspinal masses, which are typically discovered incidentally. Paraspinal masses are the most common site of EMH after hepatosplenomegaly and the most common site to present as a mass. Thoracic masses in the chest are frequently associated with thalassemia. The thoracic paraspinal masses of EMH are typically bilateral, smooth-surfaced, soft-tissue masses that contain areas of fat attenuation and do not calcify. The presence of fat attenuation within the masses most likely represents non-active lesions (akin to yellow marrow), whereas enhancement is more likely to be present in actively haematopoietic masses (akin to red marrow). Paravertebral masses are much more common in the thorax than in the abdomen or pelvis. The differential diagnosis of masses in the posterior mediastinum is led by neurogenic tumours and lymphoma, which can often have a similar appearance. Unlike lymphoma, EMH will present with bilateral masses and no soft-tissue connection or isthmus between the two masses. Neurogenic tumours are more commonly associated with osseous erosion. Castleman's disease is an additional possible differential diagnosis; however, the heterogeneity of masses associated with EMH is a key discriminator.
- References
- 1. Roberts AS, Shetty AS, Mellnick VM, Pickhardt PJ, Bhalla S, Menias CO. Extramedullary haematopoiesis: radiological imaging features. Clin Radiol. 2016 Sep;71(9):807-14.
- Please refer to
- Case 1011 Case 898 Case 708 Case 598
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- Keywords
- Extramedullary Hematopoiesis,