Parietal Plasmacytoma: An Ominous Sign of Disease Recurrence

Plasmacytomas located in the central nervous system are rareentities; with no pathognomonic clinical or radiologic features histology is required for a definite diagnosis. We present a case of a dural plasmacytoma as the manifestation of disease recurrence in a patient with systemic multiple myeloma. 51 year old male with history of IgG kappa myeloma, who underwent complete remission after an autologous bone marrow transplant presented to the clinic 10 months post-remission complaining of a “head mass”. On physical examination, he was found to have a large soft mass in the parietal area. On MRI the lesion was described as an extra-axial mass, 5.5 cm x5cm diameter, with diffuse enhancement of the dura. Biopsy of the mass revealed anextramedullary plasmacytoma. At that time, his M spike and immunoglobulins levels were unremarkable. Several months after the presentation of the parietal mass, the patient developed recurrence of disease. He underwent a second autologous bone marrow transplant that markedly improved the size of the plasmacytoma. Patient achieved a complete remission after the second transplant. However, 6 months later the dural plasmacytoma increased in size and once again and his myeloma markers remained within normal levels. Unfortunately, recurrence of the multiple myeloma occurred several months later and despite several cycles of chemotherapy, the patient continued to have progression of disease. He then decided for a more conservative treatment and was sent to home hospice. Central nervous system plasmacytomas can present as solitary lesions or as part of systemic multiple myeloma, these tumors tend to have a direct relationship with the activity of the disease and can present as an early sign of recurrence despite normal multiple myeloma markers on peripheral blood.