A 5‐year‐old child presenting with tumor‐like primary angiitis of the central nervous system

INTRODUCTION: Primary angiitis of the central nervous system (PACNS) is a vasculitis confined to the CNS. A small proportion of the lesions may present as a tumor‐like mass, which is rarely seen in children. CASE PRESENTATION: A 5‐year‐old girl was admitted to our hospital because of an intermittent headache. Brain imaging suggested a space‐occupying lesion in the right cerebral hemisphere. The final diagnosis was PACNS with a lymphocytic pattern by stereotactic brain biopsy. Her condition improved after immunotherapy. CONCLUSION: Pediatricians should consider the possibility of PACNS when encountering intracranial tumor‐like lesions. Early diagnosis of tumor‐like PACNS and prompt immunotherapy could improve the long‐term prognosis and avoid surgery.