18F-Fluorocholine (18F-FCho) to Distinguish Necrosis From Recurrence in Brain Metastases

This study will enroll patients with brain metastases that are evolving after SRS who are scheduled to undergo surgical resection. Eligible patients will undergo an 18F-FCH PET study 1-to-7 days pre-operatively. Although no toxicity has been previously reported following 18F-FCH administration, patients will be contacted 1-3 days after their scan and asked whether they experienced any adverse effects. The patients who have a positive 18F-FCH PET study (in which there is visible focal "hot spots" (a focus of lesion/normal white matter ratio >1.4) of 18F-FCH) will undergo further evaluation and be administered a second administration oflower activity 18F-FCH at the time of surgery. The purpose of the second 18F-FCH administration in the operating room is to further elucidate the tissue distribution of 18F-FCH radioactivity with respect to the histopathology of the surgically resected tissue.