Despite being a preventable disease, the public health impact of lung cancer is daunting. Lung cancer accounts for more than an estimated one million deaths each year.¹ Unfortunately, most persons with non-small-cell lung cancer (NSCLC) have unresectable disease at presentation with an overall 5 year survival rate of approximately 15%.^2,3 In contrast, 99% of patients with prostate cancer, 88% of those with breast cancer and 63% of patients with colon cancer are alive at 5 years.³ For early stage NSCLC the preferred treatment is surgical resection, with an estimated 75 000 procedures performed in the US and 3000 in the UK each year.⁴ This preference is supported by favourable 5 year survival rates for patients with potentially resectable tumours (stage IA 67%, stage IB, 57%, stage IIA 55%, stage IIB 39%).⁵ However, up to 30% of patients with stage I and 65% of patients with stage II cancers will experience recurrence within 5 years of resection.⁶ Furthermore, although recent survival rates for resected stage I and II disease have increased compared with historical controls,⁷ this has been attributed in part to more careful surgical lymph node analysis (stage migration)^8,9,10 and the detection of earlier disease (lead time bias).¹¹

Surgical resection of lung cancer with intent to cure was introduced in the early 1930s by Graham and Singer.¹² Surgery was quickly accepted as the preferred treatment modality for early stage NSCLC, based in large part on the results from observational and retrospective studies.^13,14 However, relying on these type of studies can be misleading because the apparent benefit of surgical resection may be due to patient characteristics, supportive measures and care, or other …