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Overview
Lung cancer is the leading cause of cancer-related mortality worldwide. Non-small cell lung cancer is a disease in which malignant (cancer) cells form in the tissues of the lung.
Lung cancers are thought to develop over many years. They may start as areas of pre-cancerous changes in the lung that cannot be seen on an x-ray and do not cause symptoms. Over time, these pre-cancerous changes can progress to true cancer. As a cancer develops, the cancer cells can make chemicals, which create new blood vessels nearby, which, in turn, feed the cancer cells. Eventually, the cancer cells grow and form a tumor large enough to be seen on imaging tests such as x-rays.
At some point, cells from the cancer may break away from the original tumor and spread (metastasize) to other parts of the body. Lung cancer is a life-threatening disease because it often spreads before it can be detected on an imaging test.
About 85 percent of cases of all lung cancers are the non-small cell type. Each type of non-small cell lung cancer comprises different kinds of cancer cells, which grow and spread in different ways. The types of non-small cell lung cancer are named for the kinds of cells found in the cancer and how the cells look under a microscope:
- Squamous cell carcinoma: Cancer that begins in squamous cells, which are thin, flat cells that look like fish scales. This is also called epidermoid carcinoma. About 25% to 30% of all lung cancers are this kind. They are linked to smoking and tend to be found in the middle of the lungs, near a bronchus.
- Large cell carcinoma: Cancer that may begin in several types of large cells. About 10% to 15% of lung cancers are this type. Large cell carcinoma tends to grow and spread quickly, making it harder to treat.
- Adenocarcinoma: Cancer that begins in the cells that line the alveoli and make substances such as mucus. This type accounts for about 40% of lung cancers. It is usually found in the outer part of the lung.
Other less common types of non-small cell lung cancer include:
- Pleomorphic carcinoma: A rare type of lung carcinoma featuring spindle or giant cells.
- Carcinoid tumor: Another slow-growing type of cancer made up of neuroendocrine cells, which have undergone changes that cause them to grow out of control.
Symptoms
In its earliest stages, lung cancer typically does not cause any symptoms and may be found during a routine chest x-ray. Symptoms usually occur when the disease is advanced, and may include:A cough that doesn’t go away
- Trouble breathing
- Chest discomfort
- Wheezing
- Coughing up blood
- Hoarseness
- Loss of appetite
- Weight loss for no known reason
- Bone pain
- Feeling very tired
- Headache
Diagnosis
The following tests and procedures may be used to diagnose non-small cell lung cancer:
- Physical exam and history. An examination of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits will also be taken, including smoking, past jobs, illnesses, and treatments.
- Laboratory tests. Medical procedures that test samples of tissue, blood, urine, or other substances in the body. These tests help to diagnose disease, plan and check treatment, or monitor the disease over time.
- Chest x-ray. A picture of the organs and bones inside the chest.
- CT scan (CAT scan). A procedure that makes a series of detailed pictures of areas inside the body, such as the chest, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
- PET scan (positron emission tomography scan). A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where the glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and absorb more glucose than normal cells.
- Sputum cytology. A procedure in which a pathologist views a sample of sputum (mucus coughed up from the lungs) under a microscope, to check for cancer cells.
- Fine-needle aspiration (FNA) biopsy of the lung. The removal of tissue or fluid from the lung using a thin needle. A CT scan, ultrasound, or other imaging procedure is used to locate the abnormal tissue or fluid in the lung. A small incision may be made in the skin where the biopsy needle is inserted into the abnormal tissue or fluid. A sample is removed with the needle and sent to the laboratory. A pathologist then views the sample under a microscope to look for cancer cells. A chest x-ray is done after the procedure to make sure no air is escaping from the lung into the chest.
- Bronchoscopy. A procedure to look inside the trachea and into the lungs for abnormal areas. A bronchoscope is inserted through the nose or mouth into the trachea and lungs. A bronchoscope is a thin tube with a light and lens for viewing. It may also have a tool to remove tissue samples, which are checked under a microscope for signs of cancer.
- Thoracoscopy. A surgical procedure to look at the organs inside the chest to check for abnormal areas. An incision is made between two ribs, and a thoracoscope is inserted into the chest. A thoracoscope is a thin, tube-like instrument with a light and a lens. It may also remove tissue or lymph node samples to check them for signs of cancer. In some cases, this procedure is used to remove part of the esophagus or lung. If certain tissues, organs, or lymph nodes can’t be reached, a thoracotomy may be done. In this procedure, a larger incision is made between the ribs and the chest is opened.
- Thoracentesis. The removal of fluid from the space between the lining of the chest and the lung, using a needle. A pathologist views the fluid under a microscope to look for cancer cells.
- Light and electron microscopy. A laboratory test in which cells in a tissue sample are viewed under regular and high-powered microscopes to look for certain changes in the cells.
- Immunohistochemistry study. A laboratory test in which a substance such as an antibody, dye, or radioisotope is added to a sample of cancer tissue to test for certain antigens. This type of study is used to tell the difference between varying types of cancer.
Determining Treatment Options
Treatment options depend on the following:
- The stage of the cancer (the size of the tumor and whether it is in the lung only or has spread to other places in the body)
- The type of lung cancer
- Whether there are symptoms such as coughing or trouble breathing
- The patient’s age and general health
Treatments
- Chemotherapy—for most patients with non-small cell lung cancer, current treatments do not cure the cancer. Approximately 50 percent of people have advanced disease when diagnosed and are treated solely with chemotherapy, usually platinum based. Chemotherapy uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). The way the chemotherapy is given depends on the type and stage of the cancer being treated.
- Surgery—wedge resection removes a tumor and some surrounding normal tissue; lobectomy removes an entire lobe of the affected lung; pneumonectomy removes an entire lung; sleeve resection removes part of the bronchus.
- Radiation therapy—a cancer treatment that uses high-energy x-rays, or other types of radiation, to kill cancer cells or keep them from growing. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer.
- Radiosurgery—a method of delivering radiation directly to the tumor with little damage to healthy tissue. Despite its name, it does not involve surgery and is usually used for patients who could not tolerate lung cancer surgery or would rather not have the surgery.
- Targeted therapy—a type of treatment that uses drugs or other substances, such as monoclonal antibodies, to identify and attack specific cancer cells. Targeted therapy may have fewer side effects than other types of cancer treatments.
- Laser therapy—a cancer treatment that uses a laser beam (a narrow beam of intense light) to kill cancer cells.
- Photodynamic therapy (PDT)—a drug that is not active until it is exposed to a laser light is injected into a vein. The drug collects more in cancer cells than in normal cells. Fiberoptic tubes are then used to carry the laser light to the cancer cells, where the drug becomes active and kills the cells. Photodynamic therapy causes little damage to healthy tissue.
- Cryosurgery—a treatment that uses an instrument to freeze and destroy abnormal tissue, such as carcinoma in situ (has not spread).
- Electrocautery—a treatment that uses a probe or needle heated by an electric current to destroy abnormal tissue.
Biogen Idec Investigational Treatments
- Clinical trials—using investigational treatments may be discussed as a possible treatment option for some patients, depending on the specific requirements of the different trials and the patient’s cancer stage and disease status. Click here to learn more about clinical trials. About Clinical Trials
Currently, Biogen Idec is conducting clinical trials in this disease.
For more information, click here.
To contact Biogen, click here.
Non-Small Cell Lung Cancer Resources
http://www.nlm.nih.gov/medlineplus/ency/article/007194.htm
http://www.mayoclinic.org/lung-cancer/types.html
http://www.centerwatch.com/clinical-trials/listings/studylist.aspx?CatID=683
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