TY - JOUR T1 - Evaluation of screening-detected lung nodules: minimising the risk of unnecessary biopsy and surgery JF - Thorax JO - Thorax SP - 277 LP - 279 DO - 10.1136/thx.2010.142067 VL - 66 IS - 4 AU - Michael K Gould Y1 - 2011/04/01 UR - http://thorax.bmj.com/content/66/4/277.abstract N2 - Screening for lung cancer has a long and controversial history. Successful screening is predicated on two fundamental principles.1 First, the screening test should be able to detect disease in an early preclinical phase before symptoms develop. Second, treatment should be available and more effective when provided during the preclinical phase. On the surface it would appear that screening for lung cancer passes both of these tests, given our experience with treating ‘early’ versus ‘late’ stage lung cancer that is clinically detected. However, if we acknowledge that at least some cases of clinically detected stage I and II lung cancer might represent disease that is relatively indolent biologically as opposed to ‘early’, then the possibility exists that early detection will not alter the natural history of lung cancer and result in more frequent cure. Fortunately, the hypothesis that lung cancer screening with CT scanning reduces mortality is currently being evaluated in several large randomised controlled trials in both the USA and Europe.2–6Another set of prerequisites for any screening programme is that both the screening test and any downstream testing should be convenient for patients, relatively inexpensive and without a high risk of complications. Recent attention has focused on previously discounted risks from the radiation exposure that are associated with undergoing CT screening and follow-up.7 Smith-Bindman et al estimated that the median effective radiation dose associated with a single non-contrast CT examination of the chest (8 mSV) was approximately equal to that of 117 chest x-rays and that, in 40-year-old women, one radiation-induced cancer would ultimately develop for every 720 who underwent CT.8 In a population-based analysis, Berrington de Gonzalez et al calculated that the approximately 72 million CT scans performed in the USA in 2007 would ultimately be responsible for 29 000 future radiation-induced cancers including 4100 related … ER -