Secondary extramedullary plasmacytoma in the absence of active multiple myeloma: a rare cause of small bowel obstruction.

A 75-year-old woman with a history of multiple myeloma in remission presented with signs, symptoms and imaging findings consistent with a small bowel obstruction secondary to an intussusception. She underwent operative management, and intraoperative findings were consistent with an intussusception of mid small bowel as the cause of the small bowel obstruction. The offending portion of small bowel was resected, and histopathology confirmed a plasmacytoma deposit in the small bowel at the lead point of the intussusception. Secondary extramedullary plasmacytomas in the gastrointestinal system are rare but can have significant consequences like small bowel obstruction requiring operative management. We present a rare case that emphasizes the need to be highly suspicious for uncommon sequelae of multiple myeloma like secondary extramedullary plasmacytomas when managing patients with history of multiple myeloma in remission with concerning abdominal symptoms.