Plasma cell tumors of the skull

Plasma cell tumors are rare neoplasms, which include extramedullary plasmacytoma, solitary plasmacytoma of the bone, and multiple myeloma. Although indistinguishable histopathologically, these entities need to be differentiated as treatment and prognosis vary.

This study was conducted by retrospective chart review and correspondence with patients diagnosed to have plasma cell tumors of the skull from 1992 to 2004. The clinico-diagnostic investigations, treatment, and subsequent follow-up of the patients were obtained.

We report 5 cases of plasma cell tumors of the skull. The lesion involved the base of skull in 2 and the calvarium in 3 patients. In 2 cases, the histopathology was reported as plasmacytoma and further investigations revealed systemic involvement, indicative of multiple myeloma. In 1 patient, the biopsy was reported as multiple myeloma. The above 3 patients underwent radiation, followed by chemotherapy, and there was improvement in their neurologic status at subsequent follow-up. Another patient with a scalp swelling and symptoms of systemic involvement underwent investigations to detect multiple myeloma and, hence, was not subjected to an invasive procedure for histopathologic diagnosis. Chemotherapy was initiated but was discontinued because of social reasons. The last patient in our series died in the immediate postoperative period and although her histopathology was reported as plasmacytoma, she could not be evaluated for systemic involvement.

The treatment options are different for the systemic form of disease and the localized disease; hence, it is imperative that a rigorous search for systemic involvement is conducted in a case of solitary or extramedullary plasmacytoma.