Diffuse nonsecretory osteosclerotic myeloma with extensive erythrophagocytosis.

A 51-year-old, black man presented with severe anemia and weakness. X-ray studies showed diffuse osteosclerosis involving most of his skeleton. He was documented to have similar bone changes on x-ray 5 years previously. Peripheral blood findings were suggestive of a myelophthisic anemia. Open biopsy of the iliac bone showed osteosclerotic myeloma. Secretion of abnormal protein could not be demonstrated through many examination of serum or urine. A unique finding at the autopsy was the presence of extensive erythrophagocytosis by the neoplastic plasma cells and macrophages.