Evaluation of the cost-effectiveness of lung cancer physical examination by Helical CT

From April 1996 to March 1999, 2570 men and 816 women received lung cancer examination by Helical CT. Helical CT was carried on, voltage =120 kV, current =50 mA, X-ray tube rotation rate =1 round/sec, table moving speed =20 mm/sec, WL =-700, WW =2000. On Helical CT, sixteen patients (12 males and 4 females) (0.47%) had early stage lung cancer which could not be detected by radiography. These cancers belonged to type A, type B and type C in the classification of Noguchi. Survival rate of these cancers is high, and care cost is low. Helical CT for lung cancer screening is expensive. And in patients with 50% in five-year survival rate, the cost-effectiveness was not found even sensitivity was 0.7, however, with 80% in five-year survival rate, the cost-effectiveness may be found when sensitivity was 1.0. (K.H.)