Solitary plasmacytoma of clavicle: A case report

Introduction: Plasmacytoma is a localized collection of malignant plasma cells. The disease can be divided into solitary plasmacytoma of the bone (SPB) and extramedullary plasmacytoma (EMP), both of which are distinct entities. An EMP, the rarer of the two, has soft tissue infiltration by clonal plasma cells without any occult or systemic myeloma. Whereas, SPB has a solitary lytic bone lesion with infiltration of monoclonal plasma cells, with absence of the same on a random marrow sampling or any evidence of systemic myeloma. Though SPB may involve any bone in the body but involvement of medial end of clavicle, though reported, is extremely rare. Case Report: Herein, we report a case of a 65­year­old farmer presented with pain and swelling of the medial end of the left clavicle, which was postoperatively diagnosed to be a solitary plasmacytoma by virtue of histopathology and IHC, with no other evidence of osteopenic lesions on radiographs, a negative bone scan, absence of marrow involvement by monoclonal plasma cells, presence of M­band on serum protien electrophoresis, in the IgG region and no evidence of anemia, hypercalcemia, hyperuricemia, hypercreatininemia, nephropathy, respiratory and urinary tract infections that can suggest the presence of any systemic myeloma. Conclusion: The case of solitary plasmacytoma of the clavicle reported here is a very rare as a disease entity, and rarest because of the site of involvement. The patient was treated with surgery and radiotherapy and had excellent disease control.