Over the lasat decade, PET scans have become commonplace in the staging of NSCLC. There's an older post that reviews the concept of PET scans in providing metabolic imaging, as well as a podcast that provides a more complete discussion of PET scanning in oncology, with a focus on lung cancer.
I'm very happy to present an audio interview with Dr. Eric Vallières, an excellent thoracic surgeon and Surgical Director of the Lung Cancer Program at Swedish Cancer Institute. Within the lung cancer community, he actually happens to be among the most well known thoracic surgeons in the country and even world, and he has a major expertise in the integration of chemotherapy and other systemic therapies for early stage lung cancer.
We know PET scans can provide additional metabolic information that can be more sensitive and specific for cancer than chest x-rays and even CT scans in the initial staging of lung cancer (see prior post on introduction to PET scans). PET scans are now nearly universally employed in the initial workup, at least of patients who have NSCLC and aren’t already known to have stage IV disease.
PET scans are an important way to discriminate between metabolically active nodules, suggestive of cancer but sometimes representing inflammation or infection, and non-PET-avid lesions that are felt much likely to represent cancer. They are also a cornerstone of "clinical" staging by imaging and patient exam (vs. "pathologic" staging by surgery to clarify where cancer is or isn’t).
Purists have considered mediastinoscopy, which is invasive staging of the mediastinum through a small incision just at the base of the neck to get down behind the sternum, or breastbone, to be the "gold standard" for determining whether lymph nodes in the mediastinum, or middle of the chest, is involved with a cancer. The procedure is as shown: