|
Age / Sex : 58 / M
Chief complaint: Incidentally found mass during workup for alcoholic liver disease
1) What is your impression?
Two weeks later, you can see the final diagnosis with a brief discussion of this case.
(Quiz는 quiz일 뿐이오니 답안은 한개만 보내주시기 바라오며, 복수의 답안을 보내주시는 분은 정답이 포함되어 있더라도 부득이 semi-correct answer로 처리토록 하겠습니다.)
Courtesy: 박지선(Park Ji Seon), 경희대병원(Kyunghee University Hospital)
Diagnosis: Extramedullary hematopoiesis (EMH)
Discussion
Findings:
MR and CT
scans reveal a well-defined, oval mass at right paravertebral region of T8
level. The mass has fatty component at anterior portion(; high signal intensity
on both T1W and T2W axial images, low signal intensity on fat-suppressed image,
and low attenuation on CT scan) and mild enhancement at the remained portion.
On sagittal
MR scans, the marrow of thoracic vertebrae demonstrates diffuse low signal
intensity on T1WI and intermediate to low signal intensity on T2WI, suggestive
of red marrow reconversion.
Differential Diagnosis: Neurogenic tumor, Paraganglioma
Diagnosis:
Extramedullary hematopoiesis (; EMH)
Discussion:
• Causes
– Chronic anemia(; thalassemia,
spherocytosis, sideroblastic anemia, sickle cell disease)
– Myelofibrosis, myeloid metaplasia,
polycythemia vera, leukemia, lymphoma, carcinomatosis, erythroblastosis
fetalis, Gaucher’s disease
• Locations of EMH
– Liver, spleen, lymph node
– Other organs: pleura, lung, GI
tract, breast, skin, brain, kidney, adrenal gland, mediastinum, etc.
• Findings of paravertebral EMH
– Well-defined, paravertebral
posterior mediastinal mass
– Multiplicity or bilaterality is
common
– CT: low attenuated mass, homogeneous
enhancement, no calcification or bone erosion
– MR: isosignal mass with or without
fat component, mild enhancement
– RI: markers for hematopoietic tissue(;
52Fe(PET), 111In-Chloride, 99mTc-colloid)
– DDx of posterior mediastinal masses
•
Neurogenic
tumor, lymphadenopathy, lymphoma, meningocele, gastroenteric/esophageal cyst,
gastric herniation, mesenchymal tumors, metastasis, paraspinous abscess
• Histology
– Myelopoietic cells with fat tissue,
hypervascularity
– Identical to myelolipoma
• Treatment
– Treatment for underlying disease à regression of EMH (; decreased
size, fat replacement)
– Mass excision is not recommendable,
if without complication
References:
- Berkmen YM, Zalta BA. Case 126:
extramedullary hematopoiesis. Radiology 2007;245:905-908
- Ginzel AW, Kransdorf MJ,
Peterson JJ, Garner HW, Murphey MD. Mass-like extramedullary
hematopoiesis: imaging features. Skeletal Radiol 2012;41:911-916
- De Geeter
F, Van Renterghem D. Scintigraphic
diagnosis of intrathoracic extramedullary hematopoiesis in alcohol-related
macrocytosis. J Nucl Med 1996;37:473-475
|
