This is a simple, non-invasive, yet powerful test to assess your deep lung health. It involves examining cells from a sample of sputum (phlegm coughed up from your lungs). This test is crucial for detecting abnormal cells that may signal lung cancer, or for identifying specific infections. You simply collect the sample in a sterile cup, usually first thing in the morning. This is a completely painless, proactive way to get a clear look at your lung health from a simple, self-collected sample.