What is Lung Cancer?

• Lung cancer is cancer that forms in tissues of the lung, usually in the cells lining air passages. The two main types are small cell lung cancer and non-small cell lung cancer. These types are diagnosed based on how the cells look under a microscope.
  
  Cancer begins in cells, the building blocks that make up tissues. Tissues make up the organs of the body.
  
  Normal, healthy cells grow and divide to form new cells as the body needs them. When normal cells grow old or become damaged, they die and new cells take their place.
  
  Sometimes, this orderly process goes wrong. New cells form when the body does not need them, and old or damaged cells do not die as they should. The build-up of extra cells often forms a mass of tissue called a growth or tumor. Tumor cells can be benign (not cancer) or malignant (cancer). Cancer cells spread by breaking away from the original tumor. They enter blood vessels or lymph vessels, which branch into all the tissues of the body. The cancer cells attach to other organs and form new tumors that may damage those organs. The spread of cancer is called metastasis.
  
  The estimated new cases and deaths from lung cancer (non-small cell and small cell combined) in the United States in 2008 are 215,020 new cases and 161,840 deaths.
  
  

Symptoms of Lung Cancer

• Early lung cancer often does not cause symptoms. But as the cancer grows, it takes a toll on the body and common symptoms may include:
  
  * a cough that gets worse or does not go away
  * breathing trouble, such as shortness of breath
  * constant chest pain
  * coughing up blood
  * a hoarse voice
  * frequent lung infections, such as pneumonia
  * feeling very tired all the time
  * weight loss with no known cause
  
  If you have a symptom that suggests lung cancer, your doctor must ascertain whether it is from cancer or something else. Your doctor may order blood tests and you may have one or more of the following tests:
  
  Physical exam: Your doctor checks for general signs of health, listens to your breathing and checks for fluid in the lungs. Your doctor may feel for swollen lymph nodes and a swollen liver.
  
  Chest x-ray: X-ray pictures of your chest may show tumors or abnormal fluid.
  
  CT scan: Doctors often use CT scans to take pictures of tissue inside the chest. An x-ray machine linked to a computer takes several pictures. The pictures may show a tumor, abnormal fluid or swollen lymph nodes. The only way to know with absolute certainty if lung cancer is present is for a pathologist to check samples of cells or tissue taken in a biopsy. The pathologist studies the sample under a microscope and performs other tests.
  
  

Types of Lung Cancer

• The type of lung cancer will determine how quickly it will spread and take a toll on the body.
  
  The types of lung cancer are treated differently. The most common types are named for how the lung cancer cells look under a microscope:
  
  Small cell lung cancer: About 13 percent of lung cancers are small cell lung cancers. This type tends to spread quickly.
  
  Non-small cell lung cancer: Most lung cancers, about 87 percent, are non-small cell lung cancers. This type spreads more slowly than small cell lung cancer.
  
  To find out what stage the cancer is in, your doctor will measure the lump, check to see if the cancer has spread and perform tests such as bone and lung scans and tissue or bone biopsies. The results of the tests will help you and your doctor decide on a treatment plan.
  
  

How Lung Cancer Affects the Body

• Besides the symptoms of lung cancer, which are generally due to the direct effects of the primary tumor to effects of metastatic tumors in other parts of the body or to disturbances of hormones, blood or other systems caused by the cancer, there are other issues that affect the body due to treatment depending on the type of lung cancer and whether or not it is metastatic lung cancer. The effects on the body include:
  
  Lung cancer most often spreads to the liver, the adrenal glands, the bones and the brain.
  
  Metastatic lung cancer in the liver usually does not cause symptoms, at least by the time of diagnosis.
  
  Metastatic lung cancer in the adrenal glands also typically causes no symptoms by the time of diagnosis.
  
  Metastasis to the bones is most common with small cell cancers but also occurs with other lung cancer types. Lung cancer that has metastasized to the bone causes bone pain, usually in the backbone (vertebrae), the thighbones and the ribs.
  
  Lung cancer that spreads to the brain can cause difficulties with vision, weakness on one side of the body and/or seizures.
  
  

Radiation and Chemotherapy

• Depending on the stage of the lung cancer and the growth of the tumor, the doctor may suggest chemotherapy or radiation.
  
  Chemotherapy uses chemicals that travel through the bloodstream. It affects both cancerous and healthy cells. This accounts for the many well-known side effects of chemotherapy, including nausea and vomiting, hair loss, skin problems, mouth sores and fatigue.
  
  Radiation therapy does not affect cells throughout the body the way chemotherapy does. However, it does affect healthy tissues overlying or directly adjacent to the tumor. To a certain extent, the side effects of radiation depend on which part of the body is targeted with radiation.
  
  Surgery is another alternative. It is the preferred treatment for patients with early stage NSCLC. Unfortunately, 60 to 80 percent of all patients who have advanced or metastatic disease are not suitable for surgery. Surgery has it benefits but it takes a toll on the patient. Many people experience pain, weakness, fatigue and shortness of breath after surgery. Most have problems moving around, coughing and breathing deeply. The recovery period can be several weeks or even months.