Lung cancer screening with low-dose computed tomography

Lung cancer is the most common cause of cancer death in the world, with most patients having a dismal prognosis. As many as 40 % of lung cancers are diagnosed in stage IV, with current 5-year survival rates well below 20 %. Conventional chest radiography has been historically derided as a valid screening tool for this dreaded disease. A recent National Cancer Institute-sponsored study known as the Prostate, Lung, Colorectal, and Ovarian cancer screening trial found no benefit from such screening in patients at risk. In recent years, low-dose computed tomography (LDCT) of the chest has emerged as a promising screening tool. Recent evidence from the National Lung Screening Trial (NLST) demonstrated a 20 % reduction in mortality from lung cancer in patients undergoing three rounds of LDCT screening. Opponents of lung cancer screening favor its limited use in the setting of well-designed trials claiming excessive false-positive findings, overdiagnosis, and morbidity and mortality associated with invasive testing. That notwithstanding, leading medical societies such as ASCO and ATS have positioned themselves recently in favor of screening subjects meeting the NLST criteria.