非分泌型骨髄腫

—自験例の紹介と文献的考察—

抄録

The reported cases of so-called non-secretory myeloma were collected from the literature. We excluded doubtful cases, in which Bence Jones myeloma could not be denied by repeated examinations of the concentrated urine. Based on 42 definite cases, clinical, pathological and immunological spectrums of so-called non-secretory myeloma have been discussed, comparing with those of secretory myeloma. In addition, a typical case of non-secretory myeloma has been presented.
Frequency of so-called non-secretory myeloma seemed to be less than one per cent of multiple myeloma. In so-called non-secretory myeloma, proteinuria, elevated ESR, anemia, azotemia and thrombocytopenia were found only in the small number of cases, but marked skeletal involvement was demonstrated in all cases. Hypoproteinemia, hypogammaglobulinemia and suppression of each of serum immunoglobulins were present in most cases, as in Bence Jones myeloma. The plasma cell counts of the bone marrow and frequency of their appearance into circulation were not characteristic. The morphology of the plasma cells in so-called non-secretory myeloma was indistinguishable from that in secretory myeloma. Amyloidosis was present in one of ten autopsy cases of so-called non-secretory myeloma. Twenty cases were studied by the immunofluorescent technique. Twelve cases were non-secretory type producing cytoplasmic immunoglobulin or its fragment. Seven cases were non-producing type. It was undetermined whether the remainder was non-secretory or non-producing in type. The cause of death was infection in 61 per cent of so-called non-secretory myeloma. Data as to the survival time of so-called non-secretory myeloma was controversial.
Concerning the pathogenesis of so-called non-secretory myeloma, a variety of explanations has been offered as follows:
(1) Immunoglobulin can not be synthesized in the myeloma cells, because the cellular protein-synthesizing apparatus may not operate due to defective molecular machinery or the myeloma cell may be derived from stem cell or reticulum cell which can not produce immunoglobulin.
(2) The intracellular transport and/or secretory mechanism of immunoglobulin produced is disturbed, because the intracellular proteins do not assemble into whole immunoglobulin molecules or carbohydrate which may play a important role for intracellular transport of immunoglobulins will not be incorporated in immunoglobulin molecules.
(3) Non-antigenic immunoglobulin fragments are produced and they can not be detected by current methods.
The studies on the pathogenesis of so-called non-secretory myeloma will give us an important clue to the mechanism of antibody formation.