[Bone marrow diagnostic in hairy cell leukaemia (author's transl)].

Evaluation of the histologic changes of the bone marrow and clinical data of twelve male and two female patients with hairy cell leukamia before treatment. Mean age of the patients was 46 years, time from the onset of symptoms 5.5 months. 13 of the patients were anaemic, showing splenomegaly, 12 suffered from thrombopenia, 9 from granulocytopenia, and 8 from hepatomegaly. In all of the cases, the relative numbers of lymphocytes in the blood had been increased together with various amounts of characteristic hairy cells. All of the cases had a typical histologic picture of lymphocytic bone marrow infiltration, mostly of the diffuse type. In 50% of the cases not only the well known rod-like intracellular inclusions could be seen, but also ring-shaped figures whose significance is discussed. Decrease of the granulopoiesis, disintergration of the marrow sinusoids, and osteoporosis are the most important additional signs. The progression of the disease is marked by increasing bone marrow infiltration, by splenohepatomegaly, anaemia, thrombopenia, and increasing numbers of typical lymphocytes in the blood. The bone marrow being considered to be the origin of the disease for good reasons, the histobiopsy of this organ ranks among the diagnostic and prognostic measures to be taken at first sight.