Abstract
We present a case of intrathoracic extramedullary hematopoiesis. The case was a 65-year-old man in whom bilateral posterior mediastinal masses were incidentally detected during treatment for gastric ulcer. The masses contained a fat component, and we considered the possibility of a malignant tumor, such as liposarcoma, so we performed a thoracotomy for the right-sided mass.
The mass was very fragile and bled easily. The pathological findings were intrathoracic extramedullary hematopoiesis. Since the left-sided mass was considered to be the same as on the right side, 111In scintigraphy was performed for a diagnosis. 111In scintigraphy showed an abnormal accumulation in the left-sided mass, also diagnosed as extramedullary hematopoiesis. We should avoid unnecessary surgery for a posterior mediastinal mass with a fat component, and 111In scintigraphy is a helpful examination for extramedullary hematopoiesis.
