A 10 year follow-up of semi-annual screening for early detection of lung cancer in the Erfurt County, GDR.

A prospective and controlled study for early detection of lung cancer in the county of Erfurt with a follow-up of 10 years is presented. A collective of 41,532 males born between 1907 and 1932 was screened by chest fluorography at 6 month intervals and compared with a control group consisting of 102,348 males of the same age, who were screened at intervals of about 18 months. No significant reduction of overall mortality and of lung cancer mortality was achieved. Semi-annual screening brought about a higher detection rate (9%/6.5%), an increase in the resection rate (28%/19%) and higher 5 and 10 year survival rates (52%; 27%/39%; 19%) of resected patients than screening in 18 month intervals. Among those patients who refused resection or were surgically untreatable, the difference in survival rates between the two investigation groups lasted only up to the 12 months barrier. This is regarded as the effect of the lead-time bias. Fluorographic screening is effective only in patients with peripheral cancers. Patients resected for central lung cancers did not show differences in the survival rates. In both investigation groups considered together surgical therapy was possible mainly in those patients who had been detected by screening (resection rate: 48%; 5 yr survival rate: 26.9%). The resection rate of all the others amounted to 9%, the 5 yr survival rate to 1.4%. Therefore we consider fluorography to time as the only chance for lung cancer control of high risk groups in spite of the absence of reduction of lung cancer mortality.