A Patient with Synchronous Gallbladder and Bone Plasmacytoma.

Multiple myeloma (MM) is the most common primary bone-originating tumor, whereas extramedullary plasmacytoma (EMP) is a plasma cell tumor that arises outside the bone and is most commonly found in the head and neck area. Gastrointestinal and particularly gallbladder involvement is exceedingly rare, and symptoms, if any are present, are usually similar to those seen with cholelithiasis. Treatment options usually include surgical resection and/or chemotherapy.