[Diagnosis of lung cancer. Role of PET/CT fusion scan in lung cancer].

Whole-body positron emission tomography (PET) with radiolabeled [18F]-fluoro-2-deoxy-D-glucose (18FDG) plays an important role in the diagnosis, staging, and management of lung cancer. The preferential accumulation of FDG in malignant cells assists in the differentiation of benign and malignant tissue. However, PET alone does not allow an accurate anatomic localisation of FDG uptake. The combination of PET with CT images improves the spatial resolution, sensitivity and specificity of the test. PET/CT, as with PET alone, is indicated for the diagnosis of pulmonary nodules as well as the locoregional and extrathoracic staging of non-small-cell lung cancer (NSCLC). In many published studies, PET/CT has been shown to be superior to CT alone, to PET alone, or to both imaging techniques used separately to evaluate pulmonary nodules or for staging NSCLC. Now, PET/CT imaging is being investigated in the staging and management of small-cell lung cancer, in radiation treatment planning, in response prediction following treatment and in the detection of lung cancer recurrence in NSCLC. PET/CT is likely to have an important role in the management of lung cancer. New machines are in development and new radiopharmaceutical agents must be assessed.