Staging of Non–Small-Cell Lung Cancer with Integrated Positron-Emission Tomography and Computed Tomography

BACKGROUND: We compared the diagnostic accuracy of integrated positron-emission tomography (PET) and computed tomography (CT) with that of CT alone, that of PET alone, and that of conventional visual correlation of PET and CT in determining the stage of disease in non-small-cell lung cancer. METHODS: In a prospective study, integrated PET-CT was performed in 50 patients with proven or suspected non-small-cell lung cancer. CT and PET alone, visually correlated PET and CT, and integrated PET-CT were evaluated separately, and a tumor-node-metastasis (TNM) stage was assigned on the basis of image analysis. Nodal stations were identified according to the mapping system of the American Thoracic Society. The standard of reference was histopathological assessment of tumor stage and node stage. Extrathoracic metastases were confirmed histopathologically or by at least one other imaging method. A paired sign test was used to compare integrated PET-CT with the other imaging methods. RESULTS: Integrated PET-CT provided additional information in 20 of 49 patients (41 percent), beyond that provided by conventional visual correlation of PET and CT. Integrated PET-CT had better diagnostic accuracy than the other imaging methods. Tumor staging was significantly more accurate with integrated PET-CT than with CT alone (P=0.001), PET alone (P<0.001), or visual correlation of PET and CT (P=0.013); node staging was also significantly more accurate with integrated PET-CT than with PET alone (P=0.013). In metastasis staging, integrated PET-CT increased the diagnostic certainty in two of eight patients. CONCLUSIONS: Integrated PET-CT improves the diagnostic accuracy of the staging of non-small-cell lung cancer.