Intracellular Protein Resembling Russell Bodies in Malignant Lymphomas Associated with Acquired Hemolytic Anemia

Large amounts of intracellular periodic acid-Schiff positive protein, closely resembling Russell bodies tinctorially and histochemically and, to varying degrees, morphologically, were found in the neoplastic cells of three patients with malignant lymphoma associated with acquired hemolytic anemia. Direct Coombs tests were positive in all three of these patients, and in two of them, immune autoantibodies against red cells were observed in unusually high titers. One of the latter also had abnormally high serum globulin levels with cryoglobulinemia.

A similar intracellular protein was present in the neoplastic tissue of seven of a control group of 65 unselected cases of malignant lymphoma. The serum globulin was elevated in four of the seven patients and one of these also had cryoglobulinemia. Definite evidence of hemolytic anemia was noted in one, and suggestive evidence in two of these four patients. A lymph node removed from a fifth patient, on whom no serum protein determinations had been made, showed hemosiderosis and marked erythrophagocytosis. This patient had not received blood transfusions or other treatment before biopsy was performed.

On the basis of our observations, it is suggested (1) that under certain conditions the neoplastic cells of malignant lymphomas are capable of synthesizing abnormal proteins; (2) that the presence of Russell body-like intracellular PAS-positive material in the neoplastic cells may be the morphologic manifestation of this protein synthesis; (3) that these abnormal proteins may play an important part in the immunological mechanisms responsible for the development of acquired hemolytic anemia in association with malignant lymphomas.