[Simultaneous presentation of multiple myeloma and acute myelomonocytic leukemia in the absence of previous chemotherapy. Description of a case and review of the literature].

A case of simultaneous occurrence of multiple myeloma and acute myelomonocytic leukaemia without previous chemotherapy is reported. A careful search of the literature disclosed 16 other cases of the same association. The possible relationships between these two haematopoietic neoplasms are discussed. On the literature and personal data, it is concluded that in course of multiple myeloma the association with an acute myeloblastic leukaemia is due to two possibilities: the first, more frequent, is the long-term effect of chemotherapy, while the second, rare, is that, by still unknown causes, a simultaneous neoplastic development of a plasma cell and myeloblastic clone occurs.