ABSTRACT
Lung cancer is a major cause of cancer death among both genders in all around the world. Radiotherapy (RT) is an important component of the multidisciplinary approach to lung cancer treatment. Although computed tomography (CT)-based planning is the current minimum standard in lung cancer radiotherapy, in addition to the anatomical information provided by CT, thanks to the integration of fluorine-18 fluorodeoxyglucose (F-18 FDG)-labeled positron emission tomography/computed tomography (PET/CT) when transferred to RT, biological characteristics of the tumor also provide important information in treatment planning and tumor identification. The contributions of F-18 FDG PET/CT to lung cancer RT can be listed as follows: (i) It has an important role in accurate staging of the disease before the RT decision is made (ii) PET/CT provides invaluable information for the determination of tumor and involved lymph nodes in RT planning (iii) PET/CT allows dose-escalation in tumor tissue (iv) PET/CT has an important role in evaluating RT response and detecting residual/recurrent disease. In this review, the role of F18- FDG PET/CT in RT treatment planning is explained in accordance with current literature data.