Solitary skull lesion as the initial presentation of multiple myeloma: A case report and review of the literature

Background: Multiple myeloma is a plasma cell neoplasm characterized by osteolytic skeletal destruction that can involve the calvarium. Skull involvement is often multifocal during the disease course, but initial presentation as a solitary enlarging skull lesion producing progressive scalp swelling is rare. In such suspected neoplastic skull lesions, gross total resection to obtain tissue for histologic diagnosis while addressing cosmesis is a key consideration in patients with a good prognosis. We report the case of a patient whose initial manifestation of multiple myeloma was a solitary skull lesion. Case Description: We describe the clinical presentation, imaging, operative technique, and postoperative course of a 63-year-old woman who presented with a slowly enlarging frontal scalp mass and was found to have a calvarial lesion with epidural extension. She underwent en bloc craniectomy and immediate synthetic cranioplasty, with histopathologic and hematologic work-up confirming multiple myeloma; written informed consent for publication was obtained, and there was no conflict of interest between the authors and the patient. Conclusion: This case underscores that multiple myeloma should remain in the differential diagnosis of solitary skull lesions presenting with scalp swelling. Gross total resection with deliberate dural preservation and simultaneous synthetic cranioplasty provided tissue for definitive diagnosis, relieved mass effect, limited local disease spread, and achieved a durable cosmetic result in a patient subsequently treated with systemic therapy.