Lung cancer is the uncontrolled growth of abnormal cells that start off in one or both lungs; usually in the cells that line the air passages. The abnormal cells do not develop into healthy lung tissue, they divide rapidly and form tumors. As tumors become larger and more numerous, they undermine the lung’s ability to provide the bloodstream with oxygen. Tumors that remain in one place and do not appear to spread are known as "benign tumors".
Malignant tumors, the more dangerous ones, spread to other parts of the body either through the bloodstream or the lymphatic system. Metastasis refers to cancer spreading beyond its site of origin to other parts of the body. When cancer spreads it is much harder to treat successfully.
Primary lung cancer originates in the lungs, secondary lung cancer starts somewhere else in the body, metastasizes, and reaches the lungs. They are considered different types of cancers and are not treated in the same way.
1) SMOKING The Center for Disease Control and Prevention reports that 160,000 smokers acquire lung cancer each year. The estimate for people exposed to second-hand smoke is 3,000 per year.
2) RADON The second largest contributor to lung cancer is radon. Radon gas detection is difficult because it can not be seen or smelled. Radon is the result of uranium decay. It travels as a gas through foundation cracks and into the air. There are ways to eliminate the danger of radon gas in private homes and buildings by installing a vent pipe, and a fan that will disseminate the gas away from the foundation and into the air.
3. Asbestos It is the third known cause of lung cancer. The use of the product has been restricted since the 1970s, but cases of mesothelioma, the lung cancer caused from asbestosis, is still very prevalent.
4. Radioactiveoris (uranium) found in mining are a known carcinogen.
5. Chemical carcinogens such as benzene and coal are found in many work places.
6. Radiation from chest x-rays can cause lung cancer.
7. Arsenic, a metal used in pesticides is a known carcinogen.
8. Dietary supplements are included in the list of carcinogens. Cases have shown that smoking and beta carotene do not mix and increases the risk of lung cancer.
9. Air pollution is known to cause 5% of all lung cancer cases.
- A cough that does not go away or gets worse.
- Chest pain that is often worse with deep breathing, coughing, or laughing.
- Weight loss and loss of appetite.
- Coughing up blood or rust-colored sputum (spit or phlegm)
- Shortness of breath.
- Feeling tired or weak.
Surgery with removal of the entire lobe in which the tumor is located, is the primary treatment for patients with early-stage cancer who are in good general health. The goal of surgery is to totally eliminate all the tumor cells and thereby provide a cure. Unfortunately, lung cancers tend to develop in smokers more than 50 years of age, who very often have other lung disease or serious medical conditions that magnify the risk of surgery. The location and size of a lung tumor dictate how extensive the operation must be. Open thoracotomy or less invasive video-assisted thoracic surgery, using smaller incisions, may be recommended for appropriately selected patients.
Lobectomy— removal of an entire lobe of the lung — is an accepted procedure for removing lung cancer when the lungs are functioning well. The mortality risk is 3 percent to 4 percent, and tends to be highest in older patients. If lung function prohibits lobectomy, a small cancer confined to a limited area can be removed with a small portion of surrounding lung tissue. This is called a sublobar resection, and may be either a wedge resection or a segmentectomy. There is a possible higher risk of recurrence with more limited surgery than a lobectomy.
, or radiotherapy, delivers high-energy x-rays that can destroy rapidly dividing cancer cells. It has many uses in lung cancer:
- As primary treatment
- Before surgery to shrink the tumor
- After surgery to eliminate any cancer cells that remain in the treated area
- To treat lung cancer that has spread to the brain or other areas of the body
Besides attacking the tumor, radiotherapy can help to relieve some of the symptoms the tumor causes such as shortness of breath. When used as an initial treatment instead of surgery, radiotherapy may be given alone or combined with chemotherapy. Today, many patients who have a small localized lung cancer, but who are not candidates for surgery, are being treated with a radiation treatment technique known as stereotactic body radiation therapy (SBRT).
involves drugs that are toxic to cancer cells. The drugs are usually given by direct injection into a vein or through a catheter placed in a large vein. Often given after surgery to sterilize microscopic disease, chemotherapy also may slow tumor growth and relieve symptoms in patients who cannot have surgery. Newer biologic agents, which may have fewer side effects than traditional chemotherapy and in some instances may be just as effective, are being used. This treatment is used in all stages of lung cancer and can prolong life even in elderly persons as long as they are in good general health. Some chemotherapy drugs increase damage done to tumors by the radiation treatment of cancer cells. Others keep the tumor cells at a stage where they are most susceptible to radiation treatment, or impair the ability of cancer cells to repair themselves after a course of radiation therapy. Evidence is mounting that a combination of these drugs integrated with radiotherapy is more effective than radiotherapy alone, but there is a substantial risk of serious side effects. Chemotherapy may cause significant side effects, such as nausea with vomiting and damage to the white blood cells that are needed to combat infection, but there now are ways to counter and treat most of these effects.
It is extremely important to remember that "inoperable" does not mean "incurable" when it comes to lung cancer. In fact, an increasing number of patients are being treated with a non-surgical approach across all stages of this disease. The effectiveness of the treatment depends on the stage of disease. In early stage inoperable disease that is treated with radiotherapy alone, control of disease is the norm. In more advanced disease, a combination of chemotherapy and radiation is delivered with curative intent. Cure rates are lower, but still possible even with disease spread to the lymph nodes within the chest. The medical or radiation oncologist may propose a combination of chemotherapy and radiation therapy for a patient who is normally active.
When cure is not a possibility, palliative treatment often is recommended. This is the use of medications, chemotherapy, radiation therapy or other measures to relieve symptoms of lung cancer without actually eliminating the tumor. The doses of radiation therapy used are smaller in order to avoid side effects. At some point, if you and your oncologist or primary care physician agree that active treatment no longer is advisable, hospice care can provide comfort and support. Pain relief is a very important part of treating lung cancer. Although many effective treatments are available and there are devices for delivering medication on demand without overdosing, many cancer patients still do not receive adequate pain relief. If the needs of the patient are clearly expressed, the treating physicians can better provide appropriate care.