Fluoroethyltyrosine in Detecting Tumors in Participants With Recurrent Intracranial Tumors

This phase II trial studies how well F-18 fluoroethyltyrosine (fluoroethyltyrosine) works in detecting tumors in participants with intracranial tumors that have come back. Imaging agents, such as fluoroethyltyrosine, may help doctors see the tumor better during a positron emission tomography (PET) scan.

PRIMARY OBJECTIVES: I. To determine if F-18 fluoroethyltyrosine (FET) PET can differentiate between benign treatment-related changes and recurrence in comparison to pathology alone in population 1. II. To determine if FET PET can accurately differentiate between low-grade and high-grade glial neoplasms in population 2. SECONDARY OBJECTIVES: I. To determine if FET PET can differentiate between benign treatment-related changes and recurrence in comparison to pathology or imaging follow-up in population 1. II. To determine if FET PET can differentiate between benign treatment-related changes and recurrence in comparison to pathology alone in population 1 patients with recurrent low-grade gliomas (grades 1 and 2). OUTLINE: Participants receive F-18 fluoroethyltyrosine intravenously (IV) over approximately 1 minute and undergo PET over 40 minutes. After completion of study treatment, participants are followed up periodically.