A rare and unique case of aggressive IgE-λ plasma cell myeloma in a 28-year-old woman presented initially as an orbital mass

Abstract

A 28-year-old African-American woman presented with new onset of left exophthalmos and diplopia. Computed tomography of the head showed a solitary mass in the left orbit. Excisional biopsy revealed a diffuse infiltrate composed of exclusively λ-restricted monotypic plasma cells based on morphology and immunohistochemistry, consistent with a plasma cell neoplasia. A subsequent staging bone marrow biopsy showed involvement of the bone marrow by λ-restricted monotypic plasma cells, consistent with a plasma cell myeloma. Serum protein electrophoresis and immunofixation studies on the peripheral blood showed a monoclonal band of IgE-λ; thus, an IgE-λ plasma cell myeloma was established. Additional clinical and radiologic workups showed multiple lytic bone lesions, diffuse lymphadenopathy, a pelvic mass, multiple mesenteric soft tissue nodules, and multiple pulmonary nodules, although none of the aforementioned sites was biopsied. The patient was treated with a combination of multiple chemotherapeutic agents and localized radiation due to the aggressive nature of the disease. To the best of our knowledge, this is the first case of an IgE plasma cell myeloma in a patient under the age of 30 years old presenting as a mass in an extramedullary site.