Introduction: An intracranial foreign body granuloma is a chronic inflammatory reaction, due to materials used in cranial surgery; this complication is rarely reported in neurosurgery. The definitive diagnosis is by pathological anatomy since the images are very similar to those of a brain tumor. Treatment is total resection of the lesion.

Clinical Case: A 2-year-old female patient, with a history of surgery for ventricular shunt and exeresis of a pilocytic astrocytoma, with contrast imaging study 6 months after surgery where a lesion suggestive of tumor recurrence was observed, for which she received chemotherapy with vincristine and carboplatin, without positive response. The patient presented to the examination, an extension of the base of support, Glasgow Coma Scale (GCS): 15 points. She underwent surgery, achieving total resection of the lesion. The final diagnosis was intracranial foreign body granuloma. The evolution was favorable, without neurological sequelae or residual tumor.

Conclusion: Intracranial foreign body reaction is a rare pathology but should be considered in the differential diagnosis of disease progression in neuro-oncology patients.