Advanced stage lung cancer is generally treated with anti-cancer medication called chemotherapy. Most lung cancer is caused by cigarette smoking. However, some lung cancers develop in people who never smoked or who only smoked for a short period of time. This type of lung cancer may respond to a medication called erlotinib (Tarceva). Erlotinib is an anticancer pill that is approved by the Food and Drug Administration (FDA) for use in patients with advanced lung cancer. Unfortunately, erlotinib does not work for all patients or only works for a period of time. The doctors are trying to find ways to improve the effect of erlotinib by combining it with another anti-cancer medication.