[Myeloma and osteocondensation (apropos of 2 cases)].

The authors report two cases of multiple myeloma which were typical both clinically and in the laboratory but XRay examination, on the other hand, showed appearances of osteocondensation. In the first case, XRay showed both lesions of osteolysis in the cranial vault and homogeneous condensation of D11 and L1, together with the left iliac crest. In the other case, there was osteolysis of the acetabulum together with areas of osteocondensation distributed throughout the pelvis and upper ends of the femurs, with two areas of annular fibrosis circumscribing the area of osteolysis, finally, homogeneous condensation of the skull. In both cases, bone biopsy confirmed the diagnosis of multiple myeloma showing both osteofibrosis and plasma cell infiltration of the bone marrow. This also permitted the authors to note the absence of any myelofibrosis or metamorphic neo-osteogenesis. Illustrated by these two cases, condensing multiple myeloma is a rare entity, the special clinical characteristics of which reside in its fairly frequent coexistence with peripheral neuritis which is probably similar to a para-neoplastic syndrome. The radiological appearances are mainly of four types: 1) Focal areas of bony condensation. 2) Areas of annular fibrosis circumscribing osteolysis. 3) Appearances of radial spicules, or 4) Osteocondensation extending to a fairly large part of the skeleton. The laboratory signs are identical with those in other types of multiple myeloma with a few exceptions, such as, rareness of hypercalcemia, more frequent tendency to hypocalcemia, rise in alkaline phosphatase, in a few cases. Bone biopsy confirms the diagnosis. The osteofibrosis resulted here from thickening of the osteoid seams by laying down of successive layers of bony substance, irregularly calcified and, also secondarily, metamorphic neo-osteogenesis in a few rare cases which also included myelofibrosis.