Genetic screening improves lung cancer treatment

CT scan of lungs

An international group of scientists has identified three genetic regions that predispose Asian women who have never smoked to lung cancer. The finding provides further evidence that risk of lung cancer among never-smokers, especially Asian women, may be associated with certain unique inherited genetic characteristics that distinguishes it from lung cancer in smokers.  
Lung cancer in never-smokers is the seventh leading cause of cancer deaths worldwide, and the majority of lung cancers diagnosed historically among women in Eastern Asia have been in women who never smoked. The specific genetic variations found in this study had not been associated with lung cancer risk in other populations.
Although environmental factors, such as secondhand smoke (also known as environmental tobacco smoke) or exhaust from indoor cooking are likely account for some cases of lung cancer among Asian women who have never smoked, they explain only a small proportion of the disease. 
About 10 to 20 per cent of all lung cancer patients carry a mutated epidermal growth factor receptor gene that speeds tumor growth. That number rises to about 40 per cent among all East Asians with non-small-cell lung cancer, the most common type. Among non-smoking East Asian women from China, Japan, Taiwan and Korea, it rises to between 60 and 80 per cent.The mutated gene drives tumor growth and yet also responds to a line of drugs called tyrosine kinase inhibitors, or TKIs.Previously, TKI medication was given to all cancer patients in the hopes of slowing its spread, but targeting patients through genetic testing is proving to be more effective.The treatment won’t eradicate cancer, but can prolong lives