Accurate staging of patients with non-small cell cancer (NSCLC) is of fundamental importance both for the correct choice of treatment plan and for prognosis. Numerous studies have demonstrated the added value of co-registration of functional PET images and anatomical CT images using hybrid PET-CT tomographs and the consequent benefits on the choice of treatment in patients with NSCLC. Currently in most PET centers CT is performed with a "low dose" technique and is used exclusively as a transmissive source for attenuation correction and anatomical localization. The availability of new generation hybrid tomographs allows for "diagnostic" CT examinations (contrast CT) to be performed with a standard dose of radiation and with the use of intravenous and/or oral iodinated contrast medium (contrast medium). Little data is currently available on the added value of a PET-CT scan performed in a single session compared to PET-CT performed independently and, generally, subsequently to CT scan.

The objective of the study is to evaluate the ability to correctly define the accuracy in localizing and characterizing lung "lesions" in patients with confirmed NSCLC, in the staging or restaging phase, through the use of: PET-CT "low-dose" and PET contrast CT.

The effects of the two procedures on the patient's quality of life and on the costs incurred by the patient and the healthcare service will also be evaluated.

Inclusion Criteria:

• patients with histologically proven NSCLC, undergoing staging or restaging;
• plasma creatinine normal;

Exclusion Criteria:

• patients with lung microcytoma;
• pregnant women

Adult patients with non-small cell lung cancer undergoing PET and contrast-enhanced CT during staging or restaging.