Feasibility of a screening programme for lung cancer among workers previously heavily exposed to asbestos

BACKGROUND: We evaluated the feasibility and costs of a screening programme with spiral CT for the early diagnosis of lung cancer among workers previously heavily exposed to asbestos. METHODS: We invited 2000 workers, 1165 (58%) of whom accepted. Women and individuals with incomplete information were excluded; 1119 subjects (mean age, 57 years) entered the main analysis. Subjects with non-calcified lung nodules and/or dubious pleural plagues (No=338) entered a post-screening diagnostic protocol based on radiological follow-up. RESULTS: Twenty-five biopsies were performed (13 pulmonary, 9 pleural, 3 combined) revealed 5 cases of lung cancer (including 1 in stage IA). The positive predictive value of the screening test was low (31%) despite its known high sensitivity (100%) and specificity (99%). Incidence of lung cancer was similar to that registered among male residents of the Veneto Region aged 55 to 59 years. The cost of the programme was Euro 1,000 per screened subject and Euro 245,000 per diagnosis (total cost, Euro 1,181,310). The total radiation dose administered to healthy subjects was about 1,100 mSv (220 mSv per lung cancer diagnosis). CONCLUSIONS: This screening programme was ineffective due to the low participation rate, the small number of diagnoses, low predictive value, and high costs.