Scalp metastasis from atypical meningioma: A case report and literature review.

Meningiomas are tumors of the meninges that originate in the arachnoid layer from arachnoid cap cells. Atypical meningiomas, classified as WHO grade 2 tumors, tend to metastasize and recur if not surgically managed properly. Scalp metastasis is a rare occurrence that presents as a subcutaneous elevation. A 33-year-old patient presented with a complaint of a constant, dull pressure headache persisting for the past 12 months, exacerbated by exertion, along with seizures and neuropsychiatric symptoms. The patient had no significant medical history but had undergone surgery 4 years ago for a WHO grade 2 meningioma. The current brain MRI revealed a dural tail sign, along with masses on both the left and right sides of the frontal lobe, extending to involve the skin on the forehead and scalp. The patient underwent surgical resection and adjuvant radiation therapy. At the 12-month follow-up, no neurological deterioration or tumor recurrence was observed. A literature review on scalp metastasis in patients with atypical meningioma was also conducted, including eight articles published up to September 2023. The mechanism of metastasis development appears to be consistent in all eight reported cases, involving the implantation of tumor cells during resection. Therefore, there is a critical need for meticulous intra- and post-operative surgical techniques to prevent such implantation.