Table 1

Characteristics of subjects donating buccal specimens

CharacteristicCurrent smokers (n = 19)Ex- or never-smokers (n = 23)
Age (yrs)53.9 (2.5)63.0 (2.3)
Female gender (%)52.547.8
Plasma nicotine (ng/ml)11.5 (2.0)0
Plasma cotinine161.7 (19.9)0.3 (0.2)
Pack-years of tobacco exposure40.3 (6.6)43.0 (ex-smokers only)
Family history of tobacco related malignancy
 First order relative45
 Second order relative32
Dietary fruits/vegetables/tea (estimated servings/day)2.9 (0.6)2.7 (0.4)
Preexisting lung disease*48
Incident lung cancer diagnosis (%)52.569.6
  • NOTE: Mean value (±SE) for characteristics by age, gender, tobacco exposure plasma biomarkers nicotine and cotinine, cigarette pack/yrs, family history of tobacco-related malignancy (lung, head and neck, bladder, pancreas, and stomach), and historical recollection of average servings of fruit, vegetables, and tea.

  • * Preexisting lung disease recorded as positive if historical diagnosis was chronic obstructive pulmonary disease (excluding asthma) or interstitial lung disease and fraction of subjects with a lung cancer diagnosis.

  • Among lung cancer incident cases in ex- or never-smokers, 15 of 16 cases occurred in former smokers, and only one of 16 occurred in a never-smoker.