Extramedullary plasmacytoma of the thyroid, refractory to radiation therapy and treated with bortezomib

Abstract

Plasma cell neoplasms involving tissues other than the bone marrow are known as extramedullary plasmacytoma (EMP).1 EMPs mostly involve the head and neck region.2 Solitary EMP involving only the thyroid gland is very rare.3,4 Because of the limited knowledge about this condition and its rarity, its management can be challenging and is often extrapolated from plasma cell myeloma.5,6 In general, surgery or radiation are considered as front-line therapy.3,5 EMPs usually respond well to radiotherapy with almost complete remission. No de…nite guidelines outlining the treatment of radio-resistant EMP of the thyroid have yet been published. Data supporting the use of chemotherapy is particularly limited.4,7,8 Here, we describe the case of a 53-year-old woman with a long history of thyroiditis who presented with rapidly worsening symptomatic thyroid enlargement. She was diagnosed with EMP of the thyroid gland that was not amenable to surgery and was refractory to radiotherapy but responded to adjuvant chemotherapy with bortezomib. ‹is report highlights 2 unique aspects of this condition: it focuses on a rare case of EMP and, as far as we know, it reports for the …rst time on EMP that was resistant to radiotherapy. It also highlights the need for guidelines for the treatment of EMPs.