Extramedullary hematopoiesis presenting as a focal splenic mass: a case report.

We report the ultrasound, computed tomographic, and magnetic resonance imaging findings in a case of extramedullary hematopoiesis presenting as a focal splenic mass in a patient with myelodysplastic syndrome. Ultrasound demonstrated a well-circumscribed hyperechoic mass, whereas computed tomography showed a heterogeneous mass better visualized after administration of intravenous contrast. On magnetic resonance imaging, the lesion was hypointense to the spleen on T1-weighted images, with increased signal on T2-weighted images, and demonstrated enhancement after intravenous contrast administration. Extramedullary hematopoiesis should be considered in the differential diagnosis for a splenic mass in any patient with a hematologic disorder.