An unusual localization of extramedullary hematopoiesis

A 37-year-old man with a history of thalassemia intermedia diagnosed 20 years earlier had fatigue, weakness, and a yellowish discoloration of the skin and sclera. On physical examination he was noted to have only mild hepatomegaly. Cirrhosis and hemosiderosis were diagnosed by liver biopsy. Tc- 99m SC bone marrow scintigraphy and SPECT imaging demonstrated an unusual accumulation of tracer in the pelvis mimicking the bladder. Two months later, In-111 demonstrated an extramedullary bone marrow site at the same location. Diagnosis was confirmed by CT scan and CT guided needle biopsy.