The association between smoking and cancer incidence in BRCA1 and BRCA2 mutation carriers |
| |
| Authors: | Kwang‐Pil Ko Shana J. Kim Tomasz Huzarski Jacek Gronwald Jan Lubinski Henry T. Lynch Susan Armel Sue K Park Beth Karlan Christian F. Singer Susan L. Neuhausen Steven A. Narod Joanne Kotsopoulos the Hereditary Breast Cancer Clinical Study Group |
| |
| Affiliation: | 1. Department of Preventive Medicine, Gachon University College of Medicine, Incheon, Korea;2. Women's College Research Institute, Women's College Hospital, Toronto, ON, Canada;3. International Hereditary Cancer Center, Department of Genetics and Pathology, Pomeranian Medical University, Szczecin, Poland;4. Department of Preventive Medicine and Public Health, Creighton University School of Medicine, Omaha, NE;5. Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Toronto, ON, Canada;6. Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea;7. Gynecology Oncology, Cedars Sinai Medical Center, Los Angeles, CA;8. Department of Obstetrics and Gynecology and Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria;9. Department of Population Sciences, Beckman Research Institute of City of Hope, Duarte, CA;10. Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada |
| |
| Abstract: | Tobacco smoke is an established carcinogen, but the association between tobacco smoking and cancer risk in BRCA mutation carriers is not clear. The aim of this study was to evaluate prospectively the association between tobacco smoking and cancer incidence in a cohort of BRCA1 and BRCA2 mutation carriers. The study population consisted of unaffected BRCA mutation carriers. Information on lifestyle including smoking histories, reproductive factors, and past medical histories was obtained through questionnaires. Incident cancers were updated biennially via follow‐up questionnaires. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using time‐dependent Cox regression models. There were 700 incident cancers diagnosed over 26,711 person‐years of follow‐up. The most frequent cancers seen in BRCA mutation carriers were breast (n = 428; 61%) and ovarian (n = 109; 15%) cancer. Compared to nonsmokers, (ever) smoking was associated with a modest increased risk of all cancers combined (HR = 1.17; 95%CI 1.01–1.37). Women in the highest group of total pack‐years (4.3–9.8) had an increased risk of developing any cancer (HR = 1.27; 95%CI 1.04–1.56), breast cancer (HR = 1.33, 95%CI 1.02–1.75), and ovarian cancer (HR = 1.68; 95%CI 1.06–2.67) compared to never smokers. The associations between tobacco smoking and cancer did not differ by BRCA mutation type or by age at diagnosis. This prospective study suggests that tobacco smoking is associated with a modest increase in the risks of breast and ovarian cancer among women with BRCA1 or BRCA2 mutation. |
| |
| Keywords: | BRCA1 BRCA2 smoking breast cancer ovarian cancer |
|
|
