BACKGROUND: Lung cancer is a common malignancy and the leading cause of cancer-related death in the Western world. 80 to 85 percent of cases are of the non-small cell histolgical type (NSCLC). Accurate staging is necessary to determine the optimal management of the disease. NSCLC is staged according to the TNM tumor classification system. Combined 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography and x-ray computed tomography (FDG-PET/CT) is an imaging technique providing both metabolical and anatomical information. Currently this modality has its most important application in cancer imaging.PURPOSE: To present an up-to-date review of the research literature concerning the use of PET/CT in NSCLC staging.METHODS: Non-systematic searches of the MEDLINE database.MAIN RESULTS: A growing body of literature has convincingly shown that PET/CT is more accurate than other imaging modalities. The advantages of PET/CT have been documented for primary tumor characterisation, for the staging of mediastinal lymph nodes and for detection of distant metastasis. On account of its significant false positive rate, PET/CT does not obviate the use of invasive techniques to stage the mediastinum and to confirm malignancy in PET/CT positive lesions. Adding PET/CT to the preoperative work-up protocol has been shown to improve patient management decisions. Thus futile thoracotomies and otherwise stage-inappropriate treatment can be prevented. PET/CT is a rather costly technique with limited availability. Therefore most published clinical guidelines recommend that its use is restricted to cases where the diagnostic yield is especially high, i.e. patients with a high pre-test probability of metastatic disease.