Introduction:Multiple myeloma (MM) is characterized by neoplastic proliferation of plasma cells that produce a monoclonal immunoglobulin [1–3]. MM presenting as an intracranial brain tumor or intracranial plasmocytoma is extremely rare, occurring in only 1% of patients. [4] It can manifest as solitary cerebral lesions, intraparenchymal infiltration, or diffuse leptomeningeal disease. In our case, we report an intracranial brain tumor of plasmacytoma that later developed into MM.Due to its rarity, the treatment of it is very heterogeneous. Thus, case reporting is important to accumulate data on this rare presentation.Case History :A 75-year-old male presented with headache and a slowly growing mass on his skull over the past year. Despite his age, he had good overall health, and neurological examination showed no abnormalities.Methods :The patient underwent an investigation that included brain computed tomography (CT) That revealed an intracranial soft tissue lesion measuring 8×7.5×5 cm over the skull’s occipital side, causing destruction of the occipital plates, as shown in Figure (1). Additional evaluation using Magnetic Resonance Venography (MRV) of the brain showed that the lesion exerted a mass effect by compressing the sagittal sinus, resulting in obstruction as seen in Figure (2). Laboratory investigations revealed several abnormalities, including anemia with a hemoglobin (Hb) level of 9 g/dL, an elevated erythrocyte sedimentation rate (ESR) of 98 mm/h, renal impairment with a creatinine level of 1.2 mg/dL, and hypercalcemia with a level of 10.5 mg/dL. Serum immunoglobulin (Ig) levels were also measured, with the results showing IgG at 601 mg/dL, IgA at 46 mg/dL, IgM at 4 mg/dL, lambda at 56 mg/dL, and κ-light chain at 995 mg/dL. A monoclonal κ-light chain was detected in both the blood and urine tests, indicating the presence of the Bence-Jones protein. Bone marrow biopsy showed almost diffuse neoplastic plasma cell infiltration, as shown in Figure (3). Immunohistochemistry confirmed CD138 positivity for plasma cells, leading to a diagnosis of MM, which was further confirmed by the presence of κ-light chains in both serum and urine.The patient underwent chemotherapy with VRD (Bortezomib 1.3 mg/m2 on days 1, 8, 11, Dexamethasone 40 mg weekly, Lenalidomide 25 mg for 21 days per cycle) for six cycles followed by five days of radiotherapy (30 GY) targeting the skull.
