title: Screening for lung cancer with low-dose helical computed tomography: anti-lung cancer association project.
abstract: OBJECTIVE
  Because efficacy of lung cancer screening using chest x-ray is controversial and insufficient, other screening modalities need to be developed. To provide data on screening performance of low-dose helical computed tomography (CT) scanning and its efficacy in terms of survival, a one-arm longitudinal screening project was conducted.
  
  
  METHODS
  A total of 1,611 asymptomatic patients aged 40 to 79 years, 86% with smoking history, were screened by low-dose helical CT scan, chest x-ray, and 3-day pooled sputum cytology with a 6-month interval.
  
  
  RESULTS
  At initial screening, the proportions of positive tests were 11.5%, 3.4%, and 0.8% with low-dose helical CT scan, chest x-ray, and sputum cytology, respectively. In 1,611 participants, 14 (0.87%) cases of lung cancer were detected, with 71% being stage IA disease and a mean tumor diameter of 19.8 mm. At repeated screening, the proportions of positive tests were 9.1%, 2.6%, and 0.7% with low-dose helical CT, chest x-ray, and sputum cytology, respectively. In 7,891 examinations, 22 (0.28%) cases of lung cancer were detected, with 82% being stage IA disease and a mean tumor diameter of 14.6 mm. The 5-year survival rate for screen-detected lung cancer was 76.2% and 64.9% for initial and repeated screening, respectively.
  
  
  CONCLUSIONS
  Screening with low-dose helical CT has potential to improve screening efficacy in terms of reducing lung cancer mortality. An evaluation of efficacy using appropriate methods is urgently required.
authors.affiliation: Cancer Information and Epidemiology Division, National Cancer Center Research Institute, National Cancer Center Hospital, Tokyo, Japan. tsobue@ncc.go.jp
authors.forename: Tomotaka
authors.initials: T
authors.lastname: Sobue
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Moriyama
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kaneko
authors.forename: Masahiko
authors.initials: M
authors.lastname: Kusumoto
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Tsuchiya
authors.forename: Ryutaro
authors.initials: R
authors.lastname: Kakinuma
authors.forename: Hironobu
authors.initials: H
authors.lastname: Ohmatsu
authors.forename: Kanji
authors.initials: K
authors.lastname: Nagai
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nishiyama
authors.forename: Eisuke
authors.initials: E
authors.lastname: Matsui
authors.forename: Kenji
authors.initials: K
authors.lastname: Eguchi
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000401:mortality; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D009367:Neoplasm Staging; D013902:Radiography, Thoracic; D012680:Sensitivity and Specificity; D013183:Sputum / Q000166:cytology; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed / Q000379:methods*