NCI Definition: A plasma cell neoplasm arising at an extraosseous site. There is no involvement of the bone marrow. It most frequently involves the oropharynx, nasopharynx, sinuses, and larynx. Other sites of involvement include the gastrointestinal tract, central nervous system, breast, skin, lymph nodes, and bladder. A minority of patients have a monoclonal gammopathy. Treatment includes radiation therapy. Progression to plasma cell myeloma occurs in a minority of patients. 
There is 1 clinical trial for extraosseous plasmacytoma, of which 1 is open and 0 are completed or closed. Of the trial that contains extraosseous plasmacytoma as an inclusion criterion, 1 is no phase specified (1 open).
Carfilzomib, dexamethasone, and lenalidomide are the most common interventions in extraosseous plasmacytoma clinical trials.
2. The AACR Project GENIE Consortium. AACR Project GENIE: powering precision medicine through an international consortium. Cancer Discovery. 2017;7(8):818-831. Dataset Version 6. This dataset does not represent the totality of the genetic landscape; see paper for more information.