Abstract
BACKGROUND: Extracranial metastasis from meningiomas is rare, with pulmonary involvement being the most frequent metastatic site. The authors present this case to highlight the diagnostic and management challenges associated with atypical meningiomas that metastasize outside the CNS, and to emphasize the importance of long-term surveillance even in patients with radiologically stable disease. OBSERVATIONS: A 33-year-old male was initially diagnosed with an intracranial atypical meningioma (WHO grade II, 2007 classification) characterized by increased cellularity, mild nuclear atypia, and a mitotic index ≥ 4 mitoses per 10 high-power fields, without brain invasion. Seven years later, he developed multiple pulmonary metastases confirmed by histopathological analysis. Given the absence of symptoms and minimal progression of pulmonary lesions over a 7-year follow-up period, the patient was managed conservatively with structured surveillance, including regular cranial MRI and chest CT imaging. LESSONS: This case demonstrates that long-term stability of pulmonary metastases from atypical meningioma is possible under conservative management. Structured surveillance with periodic cranial and thoracic imaging may be appropriate for asymptomatic patients, while reserving surgical or radiotherapy options for those with progressive or symptomatic disease. https://thejns.org/doi/10.3171/CASE25761.