Foreign body granuloma mimicking recurrent intracranial tumor: a very rare clinical entity.

Gelatin sponge, oxidized cellulose and microfibrillar collagen are used to achieve hemostasis during neurosurgical procedures. Hemostatic agents may produce clinically symptomatic, radiologically apparent mass lesions. The differential diagnosis should include the foreign body along with recurrent tumor. We present a case of intracranial hemostatic agents found in a 56-year-old male patient seven years after undergoing a craniotomy for a left posterior parietal convexity meningioma. Preoperative magnetic resonance imaging (MRI) suggested the presence of a recurrent tumor. We emphasize that although it is rare, a granuloma due to a foreign body reaction can result in a false image of tumor recurrence.