PET-CT case examples illustrating revisions of the new lung cancer staging system: What it means to physicians and patients

Learning Objectives 1. Become familiar with important revisions made to the staging system for non-small cell lung cancer. 2. Apply the new staging system in the interpretation of FDG PET-CT scans.

The International Association for the Study of Lung Cancer (IASLC) recently published the 7th edition of the TNM staging system for non-small cell lung cancer. Several revisions were made to the 6th edition that will have an effect on the way physicians interpret PET-CT scans in patients with newly diagnosed non-small cell lung cancer. We will describe the new staging system, illustrate new features on PET-CT studies, and compare the implications with the older system. Methods: A literature review was performed in an attempt to highlight the major revisions of the new staging system in comparison with the old. A review of PET-CT scans in lung cancer patients was done in order to illustrate examples of patients who would be staged differently under the new system. The most significant changes to the new staging system involve primary lung cancer patients with additional pulmonary nodules within the ipsilateral lung (downstaged) and patients with malignant pleural effusions (upstaged). Conclusion: Knowledge and understanding of the recent changes in lung cancer staging will enhance the diagnostic abilities and contributions of radiologists and nuclear medicine physicians who interpret PET-CT studies