o Lung cancer is a type of cancer that begins in the lungs. Your lungs are two spongy organs in your chest that take in oxygen when you inhale and release carbon dioxide when you exhale. .o Lung cancer is the leading cause of cancer deaths in the United States, among both men and women. Lung cancer claims more lives each year than colon, prostate, ovarian, lymph and breast cancers combined.o People who smoke have the greatest risk of lung cancer. The risk of lung cancer increases with the length of time and number of cigarettes smoked. If you quit smoking, even after smoking for many years, you can significantly reduce your chances of developing lung cancer.
o Lung cancer does not really show any signs and symptoms until the cancer is advanced.o Signs and symptoms of lung cancer may include:o A new cough that doesnt go awayo Coughing up blood, even a small amounto Shortness of breatho Chest paino Wheezingo Hoarsenesso Losing weight without tryingo Bone paino Headacheo hanges in a chronic cough or "smokers cough"
How smoking causes lung cancer ? Doctors think that smoking causes lung cancer by damaging the cells that line the lungs. When you inhale cigarette smoke, which is full of cancer- causing substances (carcinogens), changes in the lung tissue begin almost immediately. At first your body may be able to repair this damage. But with each repeated exposure, normal cells that line your lungs are increasingly damaged. Over time, the damage causes cells to act abnormally and eventually cancer may begin.
• RadiationSurgery : Radiation therapy can be used alone or with other lung cancer treatments. Sometimes its administered at the same time as chemotherapy.• Targeted drug therapy : Targeted therapies are newer cancer treatments that work by targeting specific abnormalities in cancer cells.• Chemotherapy : Chemotherapy uses drugs to kill cancer cells. One or more chemotherapy drugs may be administered through a vein in your arm (intravenously) or taken orally. A combination of drugs usually is given in a series of treatments over a period of weeks or months, with breaks in between so that your body can recover.
o IN TARGETED THERAPHY :o Although clinical and histologic features correlate with particular genetic changes, only molecular testing can definitively identify the mutations associated with targeted therapy response or resistance. Additionally, EGFR, KRAS, and ALK mutations are almost always mutually exclusive (ie, mutations of only 1 of the 3 genes occur within any individual tumor). Therefore, Quest Diagnostics offers a Lung Cancer Mutation Panel that tests for mutations in all 3 oncogenes. Individual tests for mutation detection are also available for each gene.
Mutations that occur only in an egg or sperm cell, or those that occur just after fertilization, are called new (de novo) mutations. De novo mutations may explain genetic disorders in which an affected child has a mutation in every cell, but has no family history of the disorder. A gene mutation is a permanent change in the DNA sequence that makes up a gene. Mutations range in size from a single DNA building block (DNA base) to a large segment of a chromosome Gene mutations occur in two ways: they can be inherited from a parent or acquired during a person’s lifetime. Mutations that are passed from parent to child are called hereditary mutations or germline mutations (because they are present in the egg and sperm cells, which are also called germ cells). This type of mutation is present throughout a person’s life in virtually every cell in the body.
Acquired (or somatic) mutations occur in the DNA of individual cells at sometime during a person’s life. These changes can be caused by environmentalfactors such as ultraviolet radiation from the sun, or can occur if a mistake ismade as DNA copies itself during cell division. Acquired mutations insomatic cells (cells other than sperm and egg cells) cannot be passed on tothe next generation.Mutations may also occur in a single cell within an early embryo. As all thecells divide during growth and development, the individual will have somecells with the mutation and some cells without the genetic change. Thissituation is called mosaicism.