Extramedullary plasmacytoma in the head and neck region – presentation of two cases

Abstract

<b><br>Introduction:</b> Plasma cell tumors might be present in two types: as solitary lesions (plasmacytoma) or disseminated throughout the body – multiple myeloma. The former most commonly develops in the bones containing bone marrow, rarer in different soft tissues (extramedullary plasmacytoma).</br> <b><br>Case report:</b> The first case is a 53-year-old man with a tumor of the left side of the larynx. The CT scan revealed a tumor on the left side of the larynx causing destruction of the thyroid cartilage. Oligobiopsy results – differential diagnosis included lymphoma and plasmacytoma. Based on histopathological examination and additional tests, the diagnosis was made: extramedullary myeloma. The patient was referred for further treatment to the hematology department, where he was qualified for chemotherapy and radiotherapy. The second case is a 27-year-old man with chronic rhinitis that does not respond to antiinflammatory treatment. The MRI examination revealed a pathological mass of a hyperplastic nature with enhancement after contrast administration. An endoscopic tumor biopsy was performed. Histopathological examination revealed a plasma cell tumor. The correlation of the performed tests allowed for the diagnosis of extramedullary ameloblastoma of the maxillary sinus. The patient was referred for IGRT radiotherapy treatment.</br> <b><br>Discussion:</b> Extramedullary plasmacytoma (EMP) accounts for about 3% of all plasma cell neoplasms. It is a locally invasive submucosal tumor presenting a tendency for recurrences; however, in about 16% of cases it may progress to multiple myeloma. The treatment of choice in case of EMP is radiotherapy or chemo-radiotherapy. Pan-London Haemato-Oncology Clinical Guidelines for Plasma Cell Disorder (2020) defined diagnostic criteria for extramedullary myeloma, which are also presented in the paper.</br>