Tc99m sulfur colloid scintigraphy for detection of intrathoracic extramedullary hematopoiesis in patient with beta-thalassemia major--a case report.

Abstract

Extramedullary hematopoiesis (EMH) refers to the production of blood cells outside the bone marrow and is a compensatory mechanism for bone marrow dysfunction. A 34 year-old female patient with beta thalassemia major was found to have multiple large, well-circumscribed radiopaque paravertibral mass lesions in chest radiography. Magnetic resonance imaging (MRI) of the thorax disclosed a right upper apical and two lower thoracic paraspinal mass lesions with heterogeneous isointensity on T1-weighted images and hypointensity on T2-weighted images. Because intrathoracic EMH is suspected in our case, which had obvious bone marrow dysfunction, radionuclide bone marrow scintigraphy is helpful in supporting the diagnosis. Tc99m sulfur colloid scintigraphy demonstrated three intense radioactive thoracic paraspinal mass lesions corresponding to the lesions seen on MRI. We believe whole body bone marrow scintigraphy with Tc99m sulfur colloid is the best convenient noninvasive method for supporting the diagnosis of EMH.