Multifocal Extramedullary Plasmacytoma Involving the Nasal Cavity: A Case Report and Review of the Literature

Extramedullary plasmacytomas (EMPs) are rare plasma cell neoplasms that occur within the soft tissue. Although they only account for 1-2% of all plasma cell neoplasms, 90% occur in the head and neck region. The case presented is exceedingly rare because our patient had an unusual variant of multifocal EMP involving left nasal cavity, chest wall, abdominal wall, axilla, and scrotum with the absence of bone marrow involvement. Our patient is 65-year-old man who presented to the emergency room with left-sided sinonasal mass that caused gradual worsening of vision in the left eye, ultimately leading to orbital apex syndrome and complete blindness. He underwent surgery to debulk the left sinonasal mass and decompress the medial orbital wall a week after blindness occurred, followed by chemotherapy with excellent response in the size of the mass but without significant improvement in vision.