Roentgen Manifestations of Thoracic Extramedullary Hematopoiesis

¹ Departments of Radiology and Pathology, Yale University School of Medicine and the Radiology Service of the Grace-New Haven Community Hospital

Intrathoracic masses of extramedullary hematopoietic tissue present a diagnostic problem for the clinician and the radiologist. The diagnosis should be considered especially in cases of spherocytic anemia. The pathologic findings in bone marrow and roentgenographic changes in bones due to marrow replacement or abnormal proliferation of marrow are important indicators of the diagnosis. The roentgenographic demonstration of well defined masses in the paravertebral gutter, enlarged spleen, bone changes, and a history of a severe anemia are a tetrad toward a preoperative diagnosis of extramedullary hematopoiesis. Three cases of extramedullary hematopoiesis presenting as masses in the thorax are described. Two of the cases demonstrate mediastinal masses in association with congenital hemolytic anemia. The third case was in association with myelosclerosis and the extramedullary hematopoietic mass compressed the thoracic spinal cord. This is the first known case with such a manifestation to be reported.