Among 835 subjects followed up prospectively for chronic obstructive pulmonary disease during the past 19 years, lung cancer has developed in 42 and has been histologically confirmed in 30. Follow-up averages 4.3 years or a total of 3,629 man-years. The incidence of 11.6/1,000 man-years is four to five times that reported in other series of smokers or in subjects with bronchitis. Underlying lung damage may be an important contributing factor. The symptoms of chronic obstructive pulmonary disease and the presence of minor roentgenographic abnormalities tend to conceal the evidence of cancer that is potentially curable.
(JAMA 235:621-622, 1976)