Case-control study of cumulative cigarette tar exposure and lung and upper aerodigestive tract cancers.
The development of comprehensive measures for tobacco exposure is crucial to specify effects on disease and inform public health policy. In this population-based case-control study, we evaluated the associations between cumulative lifetime cigarette tar exposure and cancers of the lung and upper aerodigestive tract (UADT). The study included 611 incident cases of lung cancer; 601 cases of UADT cancers (oropharyngeal, laryngeal and esophageal cancers); and 1,040 cancer-free controls. We estimated lifetime exposure to cigarette tar based on tar concentrations abstracted from government cigarette records and self-reported smoking histories derived from a standardized questionnaire. We analyzed the associations for cumulative tar exposure with lung and UADT cancer, overall and according to histological subtype. Cumulative tar exposure was highly correlated with pack-years among ever smoking controls (Pearson coefficient = 0.90). The adjusted odds ratio (95% confidence limits) for the estimated effect of about 1 kg increase in tar exposure (approximately the interquartile range in all controls) was 1.61 (1.50, 1.73) for lung cancer and 1.21 (1.13, 1.29) for UADT cancers. In general, tar exposure was more highly associated with small, squamous and large cell lung cancer than adenocarcinoma. With additional adjustment for pack-years, positive associations between tar and lung cancer were evident, particularly for small cell and large cell subtypes. Therefore, incorporating the composition of tobacco carcinogens in lifetime smoking exposure may improve lung cancer risk estimation. This study does not support the claim of a null or inverse association between "low exposure" to tobacco smoke and risk of these cancer types.
Department of Epidemiology, UCLA Fielding School of Public Health, Los Angeles, CA.
Travis J
TJ
Meyers
Department of Epidemiology, UCLA Fielding School of Public Health, Los Angeles, CA.|Division of Neonatal and Developmental Medicine, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA.
Shen-Chih
SC
Chang
Division of Epidemiology, Department of Public Health Sciences, University of California, Davis School of Medicine, Davis, CA.
Po-Yin
PY
Chang
Departments of Epidemiology and Environmental Health Sciences, School of Public Health and Comprehensive Cancer Center, University of Michigan, Ann Arbor, MI.
Hal
H
Morgenstern
Division of Pulmonary and Critical Care Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA.
Donald P
DP
Tashkin
Department of Epidemiology, UCLA Fielding School of Public Health, Los Angeles, CA.|Department of Pathology, David Geffen School of Medicine at UCLA, Los Angeles, CA.
Jian-Yu
JY
Rao
Departments of Preventive Medicine and Pathology, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
Wendy
W
Cozen
Departments of Preventive Medicine and Pathology, Keck School of Medicine of the University of Southern California, Los Angeles, CA.
Thomas M
TM
Mack
Department of Epidemiology, UCLA Fielding School of Public Health, Los Angeles, CA.|Healthy and At-Risk Populations Program, Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA.
Zuo-Feng
0000-0002-4669-3995
ZF
Zhang
D000230:Adenocarcinoma / Q000139:chemically induced / Q000453:epidemiology* / Q000473:pathology; D000328:Adult; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000139:chemically induced / Q000453:epidemiology* / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000139:chemically induced / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D006258:Head and Neck Neoplasms / Q000139:chemically induced / Q000453:epidemiology* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D013638:Tars / Q000009:adverse effects; D014026:Nicotiana
D013638:Tars; C024746:tobacco tar
UADT cancer; case-control studies; epidemiology; lung cancer; tobacco tar