ABSTRACT
Background Lung cancer, the commonest cancer in the world and accounting for 12.3% of all new cancer cases, is responsible for millions of deaths per year, greater than the total number of deaths from breast, colon, and prostate cancer combined. More than 160 000 patients died of lung cancer in the USA in 2005 (estimated figure of American Cancer Society). In Europe, nearly 400 000 new cases of lung cancer are diagnosed every year, and it continues to be the leading cause of cancer deaths in man above the age of 45 years.1 The 5-year survival rates are 16% in the United States and 5% in the UK. In Europe, there is substantial geographical difference in the incidence and mortality of lung cancer. Males have a four time higher chance of getting lung cancer as compared to females, and the average time of diagnosis is 61 years. The association of tobacco smoking was first reported in 1950, and it is now well established as the main cause of lung cancer, with around 90% of cases thought to be related to tobacco consumption.1-3 The strong association is related to the amount and type of tobacco product used, the duration of use, and the age at initiation.4
