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Biopsy of a reasonably well-demarcated mass of the nasopharynx demonstrates a plasma cell proliferation.
Serum electrophoresis shows a small monoclonal IgG spike. Bone marrow evaluation fails to demonstrate
plasma
cell proliferation and no lesions are seen on extensive skeletal x-rays. Which of the following is the most likely
diagnosis?
A. Heavy chain disease
B. Monoclonal gammopathy of undetermined significance
C. Multiple myeloma
D. Plasmacytoma
E. Waldenström's macroglobulinemia

D plasmocytoma?

d???

I WILL GO FOR B NOT SURE

The correct answer is D. Plasmacytoma (solitary myeloma) involving soft tissue (lungs, nasopharynx, nasal
sinuses) is a plasma cell proliferation resembling multiple myeloma but without significant metastatic
potential. In
contrast, some plasmocytomas involving bone eventually (up to 10 to 20 years) develop into frank multiple
myeloma.