A Case of Spinal Epidural Extramedullary Hematopoiesis Diagnosed Using Indium-111 Bone Marrow Scintigraphy

Although indium-111 (¹¹¹In) bone marrow scintigraphy is commonly used to assess bone marrow function, it plays a significant role in diagnosing extramedullary hematopoiesis (EMH) due to isotope accumulation in hematopoietic bone marrow. In our case, a 67-year-old man with polycythemia vera presented with an epidural tumor, for which EMH was considered a differential diagnosis. The diagnosis was subsequently confirmed by ¹¹¹In bone marrow scintigraphy. The tumors exhibited a reduction in size following radiation therapy. We report this case to highlight the utility of ¹¹¹In bone marrow scintigraphy in diagnosing EMH. This imaging modality can confirm epidural EMH and help avoid unnecessary surgeries.