CT for Diagnosis of Nodules Found in Lung-Cancer Screening Researchers have reported that small or slow-growing nodules discovered on a lung scan are unlikely to develop into tumors within two years, a finding that could help physicians determine when more aggressive scans for lung cancer are necessary. The researchers analyzed the cases of 7,557 patients at high risk for lung cancer because they were current or former smokers. All participants received multi-detector CT scans that measured the size of any suspicious-looking nodules. Patients with nodules over 9.7 millimeters in width, or those who had growths of 4.6 millimeters that grew fast enough to more than double in volume every 400 days, were recommended for further testing. Of the 196 patients who fell into that category, 70 were found to have lung cancer and 10 additional cases were found years later. However, of the 7,361 negative CT scans, only 20 cases of lung cancer later developed. From “Volume CT for Diagnosis of Nodules Found in Lung-Cancer Screening” New England Journal of Medicine (12/03/09) Mulshine, James L.; Jablons, David M.