Extramedullary hematopoiesis in the posterior mediastinum.

Intrathoracic extramedullary hematopoiesis is a rare finding seen in some cases of chronic hemolytic anemia. A case of a 56-year-old man with congenital spherocytosis and characteristic lobulated masses in the posterior mediastinum, considered to be ectopic hematopoietic tissue, is reported. Biopsy in such cases is not necessary and may be dangerous.