Scalp mass: an atypical presentation of multiple myeloma

Abstract

A 64-year-old male with no history of trauma presented to the general surgery clinic with a 6-month history of an asymptomatic left parietal scalp mass. The differential included benign etiologies such as lipoma or sebaceous cyst. At surgery, a hemorrhagic soft tissue mass with underlying defect in the parietal calvarium was noted. The initial attempt at resection was abandoned and neurosurgical consultation was requested. Magnetic resonance imaging demonstrated an enhancing scalp mass with a lytic lesion of the parietal calvarium with no intradural extension. Craniectomy with mass resection and mesh cranioplasty were performed. Pathology confirmed plasma cell neoplasm; serum protein electrophoresis and lytic skull lesions confirmed multiple myeloma. This rare presentation of multiple myeloma serves as a call for providers to maintain a broad differential when evaluating a seemingly benign mass, consider rare etiologies when appropriate and maintain vigilance for abnormal findings during any procedure.

Multiple myeloma complicated by skull plasmacytoma discovered after head injury

“…For neurosurgeons, it is challenging to associate scalp mass, which was the only chief complaint and appeared after a head injury, with a malignant-tumor-like plasmacytoma. On the one hand, although scalp masses can be the initial presentation for MM, patients typically present with additional symptoms, which include acute weakness, bone pain, and confusion [5]. In addition, not all skull plasmacytoma can present with scalp mass (e.g., lesion in skull base) [1].…”

“…Surgery can relieve compression of brain parenchyma [6] and reduce the tumor burden. However, there is a risk of bleeding due to the rich blood supply of skull plasmacytoma [4][5][6]. In addition, the tumor may be stimulated by surgery.…”