title: Lobe of origin and histologic type of lung cancer associated with asbestos exposure in the Carotene and Retinol Efficacy Trial (CARET).
abstract: Lower lobe origin and histologic diagnosis of adenocarcinoma have been described as useful parameters for attributing lung cancer to prior asbestos exposure. To assess whether these characteristics differed between asbestos-exposed individuals and smokers, we evaluated lobe of origin and histologic type of tumors in 78 asbestos-exposed and 214 nonexposed heavy smokers developing lung cancer during the Carotene and Retinol Efficacy Trial (CARET), a prospective cancer chemoprevention trial. Most tumors in both cohorts, regardless of radiographic fibrosis at baseline, originated in upper lobes, representing 67% in asbestos-exposed and 80% in smokers, respectively (adjusted OR for lower lobe = 1.41; 95% CI = 0.69-2.91). Adenocarcinoma represented 32% of lung tumors in the asbestos cohort, and 30% in the smoking cohort (adjusted OR = 0.78; 95% CI = 0.40-1.55), and was inversely associated with radiographic fibrosis (adjusted OR = 0.19; 95% CI = 0.06-0.62). We conclude that neither anatomic site nor histologic cell type of tumors distinguishes effectively between smoking and asbestos as causal factors in development of lung cancer.
authors.affiliation: University of Washington, Department of Environmental Health, Seattle, USA. werd@u.washington.edu
authors.forename: C A
authors.initials: CA
authors.lastname: Brodkin
authors.forename: J
authors.initials: J
authors.lastname: McCullough
authors.forename: B
authors.initials: B
authors.lastname: Stover
authors.forename: J
authors.initials: J
authors.lastname: Balmes
authors.forename: S
authors.initials: S
authors.lastname: Hammar
authors.forename: G S
authors.initials: GS
authors.lastname: Omenn
authors.forename: H
authors.initials: H
authors.lastname: Checkoway
authors.forename: S
authors.initials: S
authors.lastname: Barnhart
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology / Q000473:pathology*; D016588:Anticarcinogenic Agents / Q000627:therapeutic use; D015984:Causality; D015986:Confounding Factors, Epidemiologic; D004224:Diterpenes; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D009784:Occupational Diseases / Q000453:epidemiology / Q000473:pathology*; D016273:Occupational Exposure; D011446:Prospective Studies; D011658:Pulmonary Fibrosis / Q000473:pathology; D016032:Randomized Controlled Trials as Topic; D000084562:Retinyl Esters; D012907:Smoking / Q000009:adverse effects*; D014801:Vitamin A / Q000031:analogs & derivatives / Q000627:therapeutic use; D019207:beta Carotene / Q000627:therapeutic use
chemical_list: D016588:Anticarcinogenic Agents; D004224:Diterpenes; D000084562:Retinyl Esters; D019207:beta Carotene; D014801:Vitamin A; C014794:retinol palmitate