[Multiple myeloma superimposed on adult T cell lymphoma].

A 77 year-old male was admitted to the hospital because of lumbago and M-proteinemia. IgA (kappa) monoclonal protein (8,100 mg/dl) was demonstrated in serum, and Bence Jones protein (kappa) in urine samples. The bone marrow examination showed an increased number of pathological plasma cells (34. 5%). Multiple osteolytic lesions were evident on X-ray films. A diagnosis of multiple myeloma (MM) was made. He had exudative erythematous skin lesions on his back. His serum was positive for antibody to ATLA. A biopsy specimen from the skin lesions showed Pautrier's micro-abscess which were filled with Leu 3a positive T lymphocytes. 159 base pairs of human T cell leukemia virus I (HTLV-I)/pX position was identified from a cutaneous sample utilizing the polymerase chain reaction method. Thus, a diagnosis of MM superimposed on adult T cell lymphoma was made. An extensive search failed to find any cases complicated with these two diseases except a report by Tagawa et al. concerning a patient with ATL who developed IgA (kappa) MM during a five year follow up. Therefore, this is the first reported case of MM superimposed on ATL.