Lung cancer is one of the most common malignant tumors around the world. There are three main types of lung cancer – Non-Small Cell Lung Cancer, Small Cell Lung Cancer and Lung Carcinoid Tumor. Non-Small Cell Lung Cancer is the lung cancer we find in about 85% of those diagnosed, followed by Small Cell Lung Cancer at about 10-15% and Lung Carcinoid Tumor at fewer than 5%.
Lung cancers are thought to start as areas of pre-cancerous changes in the lung. The first changes in the genes inside the lung cells may cause the cells to grow faster. These cells may look a bit abnormal if we look under a microscope; however, at this point they are so small and there are no symptoms so it goes undetected. At this stage it cannot be seen on an x-ray – the good news is it’s not a cancerous tumor yet.
Abnormal cells may acquire additional mutations – this causes them to become cancer. As the cancer develops the cancer cells make chemicals that cause new blood vessels to form. These blood vessels nourish the cancer cells, which allow them to continue to grow and form a tumor large enough to be seen on imaging tests. However, new discoveries have been made – a new screening technique with low dose CT scanning is making it possible to detect lung cancer in its earliest states, when it’s most treatable.
Lung cancer has been linked to smoking. You may be eligible for CT scanning if you are constant smoker.
The lymph system is how lung cancer can spread to other areas of the body. The lymph system consists of the lymph nodes (small bean shaped collections of immune system cells that are connected by lymphatic vessels (small veins that carry lymph, opposed to blood, away from the lungs) and lymph (contains excess fluid and waste products from the body tissues, as well as immune system cells).
Lung cancer cells can enter the lymphatic vessels and begin to grow in the lymph nodes and around the bronchi and the mediastinum (the area between your lungs). Once lung cancer cells reach the lymph nodes they are on their way to traveling to other parts of your body. Treatment decisions are based on the stage of your cancer and the type of cancer you have among other things.