Uncommon Territory: Multifocal Tumor-like Brain Lesions in Granulomatosis with Polyangiitis.

Granulomatosis with polyangiitis (GPA) is a necrotizing granulomatous vasculitis affecting predominantly small vessels, typically associated with PR3-ANCA positivity. Central nervous system involvement beyond cranial nerve palsies is rare, with intracerebral granulomas being exceptionally rare and lacking specific imaging characteristics, often mimicking malignancies or other intracranial pathologies. This significantly complicates the diagnostic process, particularly in the absence of active systemic disease. We report a case of a 71-year-old woman in whom neurological symptoms and magnetic resonance imaging revealed intracerebral granulomas and led to the diagnosis of GPA. Early recognition of tumor-like brain lesions in GPA and prompt initiation of immunosuppressive and anti-edematous therapy are crucial to prevent progression and potentially life-threatening compressive complications.