Lung cancer affects a huge number of population each year. Although cigarette smoking is the main cause, anyone can develop lung cancer. Lung cancer begins when cells in the lung change and grow uncontrollably, forming a mass called a tumor, a lesion or a nodule. A lung tumor can begin anywhere in the lung. A tumor can be cancerous or benign. Once a cancerous lung tumor grows, it may or may not shed cancer cells. These cells can be carried away in blood or float away in the fluid, called lymph, that surrounds lung tissue.The natural flow of lymph out of the lungs is toward the center of the chest which explains why lung cancer often spreads there first. When a cancer cell moves into a lymph node or to a distant part of the body through the bloodstream, it is called metastasis.
People with lung cancer may experience the following symptoms or signs. Sometimes people with lung cancer do not show any of these symptoms. Or, these symptoms may be caused by a medical condition that is not cancer.
- Shortness of breath.
- Loss of appetite.
- Chest pain, if tumor spreads to the lining of the lung or other parts of the body near lungs.
- Coughing up phlegm or mucus.
- Coughing up blood.
Most people with lung cancer are diagnosed when the tumor grows, takes up space, or begins to cause problems with parts of the body near the lungs.