Scientists think they may have discovered valuable insight into why lung cancers are so hard to treat. It appears that the cancer can remain dormant for as much as two decades. A new study, published in Science, examined seven patients with lung cancer. Participants included smokers, former smokers and people who had never smoked. Research revealed that the initial genetic mutations occurred to cause the cancer were able to remain undetected for a number of years. This delay in detection allowed for other random mutations to occur which could later create a more aggressive form of cancer. Researchers think that this could explain why some people present with such severe cancers despite having previously had a clean bill of health. Current data suggests that as many as two-thirds of lung cancer patients are diagnosed with advanced stages of lung cancer, making treatment much less likely to be successful. Smoking is known to be a leading cause of lung cancer and the research indicates that smoking is largely responsible for the initial mutations in the genes. The subsequent changes to the genes that incite the rapid growth of the cancerous cells takes place were less influenced by cigarettes. The latter are thought to be driven by a protein within the tumor known as APOBEC. Information regarding the progression of the disease is instrumental in helping develop detection and treatment options, researchers say. Right now, less than 10 percent of those diagnosed with lung cancer live longer than five years. Researchers think that this is partially due to the delays in detection brought on by the dormancy period of the cells. Another reason could be that the amount of time the genes have to mutate means that the mutations are more widely varied, making targeted treatments very ineffective. Targeting one type of gene mutation merely leaves room for the others to thrive. Researchers think that detecting the disease before the cells have a chance to diversify could have the potential to vastly improve the outcome for many lung cancer patients.