68-Ga DOTATATE PET/MRI in the Diagnosis and Management of Somatostatin Receptor Positive CNS Tumors.

The study population consists of patients who undergo resection for somatostatin receptor-positive (SSTR-positive) CNS tumors, focusing on meningioma, and including esthesioneuroblastoma, hemangioblastoma, medulloblastoma, paraganglioma, pituitary adenoma, and SSTR-positive systemic cancers metastatic to the brain, such as small cell carcinoma of the lung. The study indication is to determine the diagnostic utility of 68Ga-DOTATATE PET/MRI in the diagnosis and management of patients with SSTR-positive CNS tumors, specifically whether 68Ga-DOTATATE PET/MRI demonstrates utility distinguishing between tumor recurrence and post-treatment change. To date, the utility of Ga-68-DOTATATE PET/MRI in meningioma has not been explored. Investigators have over the past 3 months been able to accrue the largest case series of presently 12 patients in whom Ga-68-DOTATATE PET/MRI demonstrated utility in the assessment of meningioma, including assessment for postsurgical/postradiation recurrence, detection of additional lesions not visualized on MRI alone, and evaluation of osseous invasion. Based on this initial experience, investigators intend to study the impact of Ga-68-DOTATATE PET/MRI in the assessment of the extent of residual tumor in patients status post meningioma resection, specifically in patients in whom tumor location limits resectability, patients with World Health Organization (WHO) grade II/III disease, and patients with history of stereotactic radiosurgery (SRS) who develop postradiation change.