Lung cancer is the leading cause of cancer death in North America, with less than 15 percent of people surviving five years after diagnosis. The prognosis is poor because there are no symptoms in the early stages of lung cancer, which often results in the disease going undiagnosed until it is too late for established treatment to be effective. To increase the survival rate, diagnosis and treatment must occur earlier. Cumulative genetic changes are believed to cause cancer. Several genetic alterations have been identified in tumours, but the genes that lead to lung cancer remain unknown. Cathie Garnis is examining genetic changes in pre-malignant tumours to identify genes that play a significant role in lung cancer progression. The results could improve understanding of the biology behind lung cancer, and ultimately help clinicians diagnose the disease earlier and develop more effective treatments.