The lungs are a pair of cone-shaped breathing organs in the chest. The lungs bring oxygen into the body as you breathe in. They release carbon dioxide, a waste product of the body’s cells, as you breathe out. Each lung has sections called lobes. The left lung has two lobes. The right lung is slightly larger and has three lobes. Two tubes called bronchi lead from the trachea (windpipe) to the right and left lungs. The bronchi are sometimes also involved in lung cancer. Tiny air sacs called alveoli and small tubes called bronchioles make up the inside of the lungs.Eighty% of lung cancers are due to tobacco smoke. There are over 2,000 known cancer-causing chemicals in tobacco smoke. Normal human cells change into cancer cells when exposed to carcinogens (chemicals which cause cancer). Other well established carcinogens of the lung include radon, asbestos, bischolomethylether, nickel, chromates, coal tar, copper radioactive materials and arsenic.
Lung cancer types:
Lung cancers are broadly classified into small cell or non-small cell. Non-small cell cancers are further divided into adenocarcinomas, squamous cell and large cell carcinomas. Approximately, 75-85% of lung cancers are non-small cell cancers and 15-25% are small cell cancers of the lung.
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.
Large cell carcinoma: Cancer that may begin in several types of large cells.
Adenocarcinoma: Cancer that begins in the cells that line the alveoli and make substances such as mucus.
1.Persistent cough and bloody sputum can be symptoms of lung cancer.
2.Lung cancer can be diagnosed based on examination of sputum, or tissue examination with biopsy using bronchoscopy, needle through the chest wall, or surgical excision.
3.The treatment of lung cancer depends on the type of cancer, its location and size as well as the age and health of the patient.
Metastasis of lung cancer is present in over 50% of patients at the time of the diagnosis of the lung cancer. The type of screening for metastatic disease depends on the patient’s cancer type, potential for complete surgical removal, the extent of cancer in the chest, and the planned therapy.
Mediastinoscopy, or looking into the central portion of the chest through a small incision made just below the collar line, is used to sample the lymph nodes in the central portion of the chest (mediastinum). This helps evaluate the extent of the tumor. If the cancer has spread to these lymph nodes, the chance of surgically curing the lung cancer is eliminated. Bone metastasis is suggested by bone pain or abnormal blood tests (elevated serum calcium, or elevated alkaline phosphatase).
X-rays or bone scans are used to evaluate the areas suspected of being cancerous. Liver metastasis may result in pain in the upper right portion of the abdomen, swelling of the abdomen, or abnormal blood tests of the liver.
The diagnosis can be made by liver scan, CAT scan or liver biopsy. Brain and spinal cord metastasis can occur with or without neurological symptoms. CAT and MRI scans of the brain and spinal cord will usually reveal these metastastic tumor sites.
Treatment choices and chances of long term survival in lung cancer depend on the type of cancer, its location and size, lymph node involvement, and whether there is evidence of cancer spread to other parts of the body outside of the lungs.
Surgery, chemotherapy, radiation
Combined chemotherapy and radiation, sometimes surgery based on results of treatment
Chemotherapy, sometimes radiation
Chemotherapy, targeted drug therapy, clinical trials, supportive care
Radiation therapy is the local treatment of cancer using various types of radioactive x-ray beams. These treatments prolong life in some patients, and improve the quality of life while relieving pain in others. It rarely cures patients of lung cancer. The major role of radiation therapy is to relieve symptoms.
Chemotherapy is called a systemic treatment because the medicines enter your bloodstream, travel through your body, and kill cancer cells both inside and outside the lung area. Some chemotherapy drugs are taken by mouth (orally), while others are injected into a vein (intravenous, or IV).Chemotherapy is widely accepted as the primary treatment for small cell cancers. In early small cell cancers of the lung, there is a higher success rate with chemotherapy, especially if the cancer is only in the chest.
Extensive research andclinical trialshave studied the different chemotherapy medicines used to treat lung cancer. Some medicines are used for most people with lung cancer. Some are used in combination with others to be more effective. Some may be used before surgery or after surgery. Your oncologist will discuss and recommend chemotherapy treatment specific to your condition. Several of the more common chemotherapy medicines include the following:
In cases of non-small cell cancers of the lung, chemotherapy can be used alone or in combination with radiation therapy.
Clinical trials tested:
Chemoprevention is the use of drugs, vitamins, or other substances to reduce the risk of developing cancer or to reduce the risk cancer will recur (come back).
Biologic therapy is a treatment that uses the patient's immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body's natural defenses against cancer.This type of cancer treatment is also called biotherapy or immunotherapy.
New combinations: New combinations of treatments are being studied in clinical trials.