Low-dose spiral computed tomography for lung-cancer screening

Abstract

Shusuke Sone and colleagues1Sone S Takashima S Feng L et al.Mass screening for lung cancer with mobile computed tomography scanner.Lancet. 1998; 351: 1242-1245Summary Full Text Full Text PDF PubMed Scopus (876) Google Scholar report that spiral computed tomography (CT) was more accurate in mass screening for lung cancer, and led to early detection and an accurate diagnosis of lung cancer, and should be considered in the future health plans. They also claim that CT identified almost ten times as many cancers (0·48%) as standard mass screening (0·03–0·05%) in the same area. Clinically the positive predictive value (PPV) is more important than the cancer detection rate, and the PPV was only 8·5% (19 cancer cases from 223 with suspicious lesions, indeterminate nodules, and suspicion of lung cancer). 91·5% of patients referred for work-up by chest radiography and high resolution CT (some with transbronchial biopsy), proved not to have the disorder. A previous study, with chest radiography and sputum cytology found a greater PPV (19%)2Fontana RS Sanderson DR Taylor WF et al.Early lung cancer detection.Am Rev Respir Dis. 1984; 130: 561-565PubMed Google Scholar and fewer false positives than Sone et al did.Randomised trials at a population level and looking at survival or quality of life should be done before spiral CT screening is introduced. Widespread implementation of unproven screening methods makes subsequent rigorous evaluation much more difficult— indeed, it may be impossible to correct the original mistake. Shusuke Sone and colleagues1Sone S Takashima S Feng L et al.Mass screening for lung cancer with mobile computed tomography scanner.Lancet. 1998; 351: 1242-1245Summary Full Text Full Text PDF PubMed Scopus (876) Google Scholar report that spiral computed tomography (CT) was more accurate in mass screening for lung cancer, and led to early detection and an accurate diagnosis of lung cancer, and should be considered in the future health plans. They also claim that CT identified almost ten times as many cancers (0·48%) as standard mass screening (0·03–0·05%) in the same area. Clinically the positive predictive value (PPV) is more important than the cancer detection rate, and the PPV was only 8·5% (19 cancer cases from 223 with suspicious lesions, indeterminate nodules, and suspicion of lung cancer). 91·5% of patients referred for work-up by chest radiography and high resolution CT (some with transbronchial biopsy), proved not to have the disorder. A previous study, with chest radiography and sputum cytology found a greater PPV (19%)2Fontana RS Sanderson DR Taylor WF et al.Early lung cancer detection.Am Rev Respir Dis. 1984; 130: 561-565PubMed Google Scholar and fewer false positives than Sone et al did. Randomised trials at a population level and looking at survival or quality of life should be done before spiral CT screening is introduced. Widespread implementation of unproven screening methods makes subsequent rigorous evaluation much more difficult— indeed, it may be impossible to correct the original mistake. Low-dose spiral computed tomography for lung-cancer screeningAuthor's reply Full-Text PDF