Armaghan Fard-Esfahani - Research Institute for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran
Mohammad Eftekhari - Research Institute for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran
Arsalan Vakili - Research Institute for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran
Mohsen Saghari - Research Institute for Nuclear Medicine, Tehran University of Medical Sciences, Tehran, Iran

Widespread studies on tumor diagnosis has led to the development of techniques with greater sensitivity and improved specificity for detection of occult and small subclinical tumors. Tumor imaging by radiolabeling of tumor-specific antibodies (Immunoscintigraphy) or tissue specific biochemical agents (Receptor imaging) and especially physiologic imaging with positron emitters (PET), have opened a new era in nuclear medicine. In this paper the latest developments in tumor imaging are reviewed.