Low-dose computed tomography screening for lung cancer in a general population: characteristics of cancer in non-smokers versus smokers

Acad Radiol. 2003 Sep;10(9):1013-20. doi: 10.1016/s1076-6332(03)00150-8.


Rationale and objectives: To report the detection rate for lung cancers in computed tomography (CT) screening in Japanese adults, and to analyze differences in the appearance of the cancers in non-smokers versus smokers.

Materials and methods: Subjects consisted of 7,847 Japanese adults who received low-dose CT screening at least once in a 3-year period. The detection rate of lung cancers and the correlation of imaging, clinical, and pathologic findings of cancers in non-smokers versus smokers were examined.

Results: The detection rate for lung cancer was 1.1% for both non-smokers (45 of 4,251) and smokers (39 of 3,596). The prevalence of well-differentiated adenocarcinomas was greater in non-smokers (88%; 22 of 25) than in smokers (29%; 4 of 14) (P < .001). The prevalence and incidence of pathologic stage IA disease were greater in non-smokers than in smokers (92%; [22 of 24] vs 58% [7 of 12], and 100% [19 of 19] vs 70% [14 of 20]) (both P < .05). The mean size of the tumors in the non-smokers (12.4 mm) was smaller than that in smokers (18.2 mm) (P < .001). The percentage of cancers categorized as pure or mixed ground-glass opacity (86%; 38 of 44) on CT was greater in non-smokers than in smokers (46%; 16 of 35) (P < .001).

Conclusion: Most of the lung cancers in non-smokers were slow-growing adenocarcinomas appearing as faint ground-glass opacities on CT, whereas rapidly growing cancers appearing as solid nodules were more commonly seen in smokers.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenocarcinoma / diagnostic imaging
  • Adenocarcinoma / epidemiology
  • Aged
  • Case-Control Studies
  • Female
  • Humans
  • Incidence
  • Japan / epidemiology
  • Lung Neoplasms / diagnostic imaging*
  • Lung Neoplasms / epidemiology
  • Male
  • Mass Screening / methods*
  • Middle Aged
  • Prevalence
  • Radiation Dosage
  • Smoking / epidemiology*
  • Tomography, X-Ray Computed / methods*