NCCN Guidelines for Patients® | Lung Cancer - Non-Small Cell Lung Cancer
8 NCCN Guidelines for Patients ® : Lung Cancer – Non-Small Cell, 2018 1 Lung cancer basics Lungs | A disease of cells You’ve learned that you have lung cancer. It’s common to feel shocked and confused. Part 1 reviews some basics that may help you learn about lung cancer. Lungs To learn about lung cancer, you first must know about the lungs. The lungs are the main organs of the respiratory system. They are involved in the exchange of gases in and out of the body. Airways Your lungs transfer oxygen—a gas that cells need to live—from the air into the blood. The blood then carries oxygen to all the cells in the body. The lungs also remove carbon dioxide—a gas made by cells— from the blood. Carbon dioxide is then exhaled from the lungs into the air. The transfer of these gases in and out of the body is called respiration. When you inhale, air travels down your throat into your windpipe (trachea). See Figure 1 . Air then enters your lungs through the bronchi. The bronchi branch off into each part (lobe) of your lung. Your right lung has three lobes and your left lung has only two lobes to make space for your heart. Within the lobes, the bronchi divide into smaller airways called bronchioli. At the end of each bronchioli are bunches of alveoli wrapped in blood vessels. The transfer of gases in and out of the blood occurs in the alveoli. Lymph Throughout your body—including in your lungs—is a clear fluid called lymph. Lymph gives cells food and water. It also contains germ-fighting blood cells. Lymph drains from tissue into vessels that transport it to the bloodstream. See Figure 2 . As lymph travels, it passes through small structures called lymph nodes. Lymph nodes remove germs from lymph. Pleura Your lungs are protected by tissue called the pleura. Pleura covers each lung and helps the lungs safely rub against other organs. Pleura is made of two layers. The outer layer is known as the parietal pleura. The inner layer is called the visceral pleura. The space in between the two layers is called the pleural cavity. It is filled with a small amount of fluid called pleural fluid. A disease of cells Your body is made of trillions of cells. Cancer is a disease of cells. Each type of cancer is named after the cell from which it derived. Lung cancer Lung cancer starts in cells of the lung. Cancers of cells from elsewhere that spread to the lung are not lung cancers. Almost all lung cancers are carcinomas. Carcinomas are cancers of cells that line the inner or outer surfaces of the body. Lung carcinomas start in cells that line the airways of the lungs. NSCLC Lung carcinomas are divided into two groups based on how the cells look. One group is called small cell lung cancer and the other group is called NSCLC ( n on- s mall c ell l ung c ancer). The second group is much more common and is the focus of this book. There are two major types of NSCLC. The first type is non-squamous carcinoma. It includes adenocarcinomas, large-cell carcinomas, and rare cell types. The second type of NSCLC is squamous cell carcinoma. It is also called epidermoid carcinoma.