The predictive value of serum myeloma protein in solitary plasmacytoma

Recurrence of solitary plasmacytoma in the liver 10 years after the onset of multiple bone lesions

A 79-year-old man presented with a history of solitary plasmacytoma in the bone 10 years ago. Chemoradiotherapy was effective, and remission was maintained with intermittent treatment at relapse of the bone lesions. One year after the last treatment, a follow-up computed tomography (CT) scan revealed multiple liver masses, and a liver biopsy revealed plasmacytoma. There was no clonal plasma cell infiltration in the bone marrow, and the final diagnosis was solitary plasmacytomas of the liver. Although liver involvement is known in relapsed refractory multiple myeloma, solitary plasmacytoma in the relapsed stage confined to the liver is rare, and all previous reports have been from the initial presentation. To the best of our knowledge, this is the first recurrent case of solitary plasmacytoma of the liver.

Posttreatment Persistence of Monoclonal Protein on Immunofixation Electrophoresis but Absence on Serum Protein Electrophoresis in a Case of Solitary Bone Plasmacytoma

Laboratory investigations for any suspected case of solitary plasmacytoma of bone include routine biochemical and hematological investigations along with β2-microglobulin, electrophoresis of serum protein and/or 24-hour urine protein, serum protein immunofixation (IFE), and nephelometric quantification of total immunoglobulin isotype and serum free light chain levels. Bone marrow aspirate and trephine biopsy are mandatory to confirm the absence of clonal plasma cells (for solitary plasmacytoma) or the presence of less than 10% clonal cells (solitary plasmacytoma with minimal bone marrow involvement). Imaging studies such as X-ray, computed tomography (CT), magnetic resonance imaging, and positron emission tomography/CT should be used to complement laboratory tests in diagnosis, staging, and defining the local extent of the plasmacytoma. However, guidelines regarding choice of technique for the detection of M band when monitoring a follow-up case of operated plasmacytoma are still not clear. Through this case study, we try to highlight the role of IFE in a follow-up case of operated solitary plasmacytoma of the bone.