Solitary plasmacytoma of bone and asymptomatic multiple myeloma.

There is a wide spectrum of disease among patients with plasma cell myeloma. A small fraction have a localized plasmacytoma of bone that requires specialized techniques for accurate staging, followed by local radiotherapy that may be curative in some patients. Other patients with multiple myeloma may be free of symptoms and the disease is recognized by chance laboratory studies. Some have a prolonged, stable course with little change in disease for many months or years and resemble patients with MGUS. These patients have low serum myeloma protein and are free of focal bone lesions even on MR imaging. Complications are more imminent among other patients with higher levels of myeloma protein and/or bone lesions, who usually require treatment within 2 years after diagnosis. Still other patients with more advanced generalized disease (intermediate tumor mass) or with a pathologic fracture that may be relieved with local radiotherapy usually require even earlier chemotherapy to prevent or treat complications.