False-positive indium 111 pentetreotide scan for recurrent meningioma due to radiation fibrosis.

A patient with recurrent meningioma in the right frontal lobe, treated with resection and radiation, had a routine magnetic resonance imaging scan that was suspicious for recurrent disease. Follow-up Octreoscan showed moderately increased focal uptake in same region, compatible with recurrence of meningioma; however, the histopathology was consistent with radiation fibrosis. There are reported cases of uptake on Octreoscans at other sites of the body due to chronic inflammation, but only one other case has been reported in the brain. Caution must be taken in interpretation of brain tumors on Octreotide scan, when treatment history includes prior radiation therapy.