Scalp mass: an atypical presentation of multiple myeloma

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.