Extramedullary plasmacytoma of maxillary sinus with later involvement of the gall bladder and subcutaneous tissues

We recently encountered a patient with extramedullary plasmacytoma (EMP) originating in the maxillary air sinus, who developed subcutaneous tissue and gall bladder involvement 2 years after initial local radiotherapy. Treatment with melphalan, prednisone and interferon led to a rapid and sustained regression of the gall bladder tumour. Complete remission was obtained by subsequent regional radiotherapy to the subcutaneous tumours in the extremities. Progression of plasmacytoma to the hepatobiliary system and subcutaneous tissues is quite rare and the effects of chemo- and radiotherapy on these lesions have not been fully elucidated. This study demonstrated that EMP can be well controlled and complete remission obtained by various therapeutic strategies, even though this tumour develops widespread dissemination.