MRI is the preferred method for the diagnosis and monitoring of brain metastases. However, MRI does not provide enough information in some important instances. We explore the potential applications of 18F-fluorodopa (18F-FDOPA) PET for patients with brain metastases. Accurate differentiation between tumor recurrence and radiation injury might be possible with the use of 18F-FDOPA PET. Semi-quantitative and qualitative parameters achieved similar results. Kinetic analysis and time-activity curve patterns could further improve accuracy. 18F-FDOPA PET also had prognostic value in this setting. Combining the high resolution of MRI with the metabolic information provided by 18F-FDOPA PET could improve recurrent tumor contouring precision for biopsy, resection or radiation. The promising applications of 18F-FDOPA PET imaging in the treatment monitoring and planning of brain metastatic tumors require further corroboration but could soon become important instruments to improve diagnostic accuracy, prognosis prediction and treatment planning of the growing population of patients with brain metastatic disease. © 2014 Informa UK, Ltd.