Unusual case of plasma cell tumor with monoclonal gammopathy of the sino-nasal cavity and clavicular bone.

A rare case of extramedullary plasmacytoma in the sino-nasal cavity is presented. During a prolonged clinical course, the tumor has recurred several times after irradiation, chemotherapy and surgery, and presented in the clavicular bone as well. Immunohistochemical staining of each tumor showed IgA kappa phenotype, and immunoelectrophoresis of the serum showed overproduction of IgA with kappa light chains. Although an elevation of serum IgA persists, the patient has remained well without evidence of overt multiple myeloma.

[Non-secretory myeloma. Report of a case with negative immunofluorescence in the tumor cells (author's transl)]. / Mieloma no secretor. Exposición de un caso con inmunofluorescencia negativa en las células tumorales.

A 39-year-old patient with bilateral paralysis of the VI cranial nerve was studied. Numerous foci of intracranial osteolysis were discovered as well as on the right calvicle and several ribs. Two bone marrow aspirates gave results within normal limits. A biopsy of the lesion on the right calvicle led to the diagnosis of myelomatosis. Immunoelectrophoresis showed that paraprotein was not present in serum and urine. Immunofluorescence with antisera marked with fluorescein was negative in the diseased bone marrow. Treatment with melphalan and prednisone given alternately produced an improvement in all of the lytic lesions within several months; 20 months after treatment was started no new destructive bony lesions have appeared. There have been very few reported cases of non-secretory myeloma. In most of these cases the presence of immunoglobulins in the tumoral cells has been shown by immunofluorescence. The absence of the immunoglobulins, as described in our case, is extremely rare. Unlike most cases of non-secretory myeloma published to date, our patient has a favorable clinical course after treatment was administered.