Metastatic carcinoma simulating agnogenic myeloid metaplasia and myelofibrosis

Eight patients with metastatic carcinoma with findings simulating agnogenic myeloid metaplasia and myelofibrosis are reported. All patients had a previous histologic diagnosis of carcinoma and complained of bone pain. All had leukoerythroblastic anemia and reticulocytosis. Splenomegaly, observed in 6 of the 8 patients, was striking in only 2. Bone marrow examination in 6 patients revealed fibrosis in all 6, and carcinoma cells were demonstrable in 4. Osseous roentgenographic changes, observed in all 8 patients, were lytic, blastic, or mixed. Clinical differentiation from agnogenic myeloid metaplasia may be difficult but is possible. Long survival after the onset of myeloid metaplasia with metastatic carcinoma may occur; 3 of our patients were living more than 2 years after onset of the disorder.