Mohsen Beheshti1, Chun K Kim2. 1. PET-CT Center LINZ, Department of Nuclear Medicine and Endocrinology, St. Vincent's Hospital, Linz, Austria. Electronic address: Mohsen.Beheshti@bhs.at. 2. Harvard Medical School, Division of Nuclear Medicine and Molecular Imaging, Brigham and Women's Hospital, Boston, MA, USA. Electronic address: ckkim@bwh.harvard.edu.