Assessing therapy response of secreting pineal germ cell tumor on simultaneous 18F-choline PET/MRI

An 18-year-old man presented with 6 weeks' history of diplopia, early morning headaches, and blurred vision; on ophthalmologic examination, Parinaud syndrome was revealed. Brain MRI scan showed a calcified pineal mass. Brain simultaneous PET/MRI with 18F-choline showed an avid enhancing mass occupying the pineal region with restricted diffusion. A second examination after chemotherapy demonstrated reduction in both size and radiotracer activity of the mass. Our study emphasizes the potential of simultaneous 18F-choline PET/MRI being a useful tool for contribution in the diagnosis and treatment assessment in a convenient way with minimal radiation exposure and reduced throughput patient time.