Extramedullary hematopoiesis (EMH) is a compensatory mechanism in response to an imbalance between bone marrow erythropoiesis and circulatory blood demand. It occurs most often due to hemolytic anemias e.g. thalassemia, hereditary spherocytosis, and sickle cell disease.

Adrenal EMH tumor should be considered in thalassemic patients with an adrenal mass, thus avoiding unnecessary surgical procedures.