Lung cancer is a type of cancer that begins in the lungs, but may spread to other areas of the body. According to MayoClinic.com, lung cancer is the leading cause of cancer deaths in the United States among both genders and causes more deaths than colon, prostate, ovarian, lymph and breast cancer combined. When lung cancer significantly invades the lungs, it can cause a chronic irritation that can lead to a severe cough.
Anatomy of the Lungs
The lungs are two large organs that play a major role in the respiratory system. When a person breathes, air travels into the nasal passages, through the trachea and into the bronchi, which are the large tubes that travel to the lungs. When the air reaches the lungs, they expand, which allows the body to get oxygen, and then deflate, which allows the body to get rid of carbon dioxide. A thin tissue, called the pleura, covers the lungs and contains a fluid called pleural fluid. When a substance, such as a tumor, interferes with this process or irritates the lung structures, a cough develops.
Physiology of Cancer
Lung cancer develops when new cells develop in the lungs when they are not needed or when old cells are not properly destroyed. The accumulation of excess cells forms a tumor, which can irritate the nerve endings in the lungs. When the nerve endings are irritated, it can disrupt proper functioning of any of the lung structures and lead to a severe cough. The body triggers the cough response in an attempt to clear the lungs of of the irritant. Unfortunately, unlike mucus, a cough cannot successfully remove cancer from the lungs.
Symptoms
One of the main symptoms of lung cancer is a severe cough, which is often classified as a cough that brings up blood or thick mucus and is accompanied by wheezing, according to MedlinePlus. The cough often starts gradually and becomes worse as the cancer advances. Those with advanced stages of lung cancer may also cough up blood. A severe cough can lead to fatigue and weakness because the coughing action requires the body to use a lot of energy, according to the National Heart Lung and Blood Institute. A severe cough can also lead to headache, chest pain, loss of bladder control and increased sweating. If the cough is extremely severe, it can cause a rib to fracture.
In addition to a severe cough, other breathing difficulties such as shortness of breath and wheezing may occur. Other symptoms include changes in voice, bone pain and unexplained weight loss.
Types
There are two types of lung cancer: small cell lung cancer and non-small cell lung cancer. Small cell lung cancer is the more aggressive of the two and occurs in heavy smokers. Small cell lung cancer usually begins in the breathing tubes. Non-small cell lung cancer is a term that encompasses several types of lung cancer, such as squamous cell carcinoma, adenocarcinoma and large cell carcinoma. Non-small cell lung cancer may occur in non-smokers. A severe cough is a common characteristic of both types of cancer.
Treatment
The National Heart Lung and Blood Institute notes that the best way to treat a cough is to treat its underlying cause. Treatment focuses on removing the lung cancer and may consist of surgery, chemotherapy, radiation therapy or a combination of the three. According to the National Cancer Institute, surgery is usually only used for very small lung tumors. People who have advanced cancer may be treated with chemotherapy alone.
