1. Body mass index, weight change, and risk of second primary breast cancer in the <scp>WECARE</scp> study: influence of estrogen receptor status of the first breast cancer
- Author
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Brooks, Jennifer D., John, Esther M., Mellemkjær, Lene, Lynch, Charles F., Knight, Julia A., Malone, Kathleen E., Reiner, Anne S., Bernstein, Leslie, Liang, Xiaolin, Shore, Roy E., Stovall, Marilyn, Bernstein, Jonine L., Capanu, Marinela, Orlow, Irene, Robson, Mark, Woods, Meghan, Boice, John D., Brooks, Jennifer, Concannon, Patrick, Conti, Dave V., Duggan, David, Elena, Joanne W., Haile, Robert W., Olsen, Jørgen H., Seminara, Daniela, Stram, Daniel O., Tischkowitz, Marc, and Thomas, Duncan C.
- Subjects
Adult ,Risk ,Cancer Research ,medicine.medical_specialty ,Population ,Estrogen receptor ,Breast Neoplasms ,lcsh:RC254-282 ,Body Mass Index ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,030212 general & internal medicine ,education ,Estrogen Receptor Status ,Original Research ,Aged ,Neoplasm Staging ,2. Zero hunger ,Gynecology ,education.field_of_study ,business.industry ,Obstetrics ,Body Weight ,Weight change ,Cancer ,Neoplasms, Second Primary ,Middle Aged ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,medicine.disease ,3. Good health ,Receptors, Estrogen ,Oncology ,Case-Control Studies ,Population Surveillance ,030220 oncology & carcinogenesis ,contralateral breast cancer ,Female ,medicine.symptom ,business ,Cancer Prevention ,Body mass index ,Weight gain ,estrogen receptor ,SEER Program - Abstract
Studies examining the relationship between body mass index (BMI) and risk of contralateral breast cancer (CBC) have reported mixed findings. We previously showed that obese postmenopausal women with estrogen receptor (ER)‐negative breast cancer have a fivefold higher risk of CBC compared with normal weight women. In the current analysis, we reexamined this relationship in the expanded Women's Environmental Cancer and Radiation Epidemiology (WECARE) Study, focusing on the impact of menopausal status and ER status of the first breast cancer. The WECARE Study is a population‐based case–control study of young women with CBC (cases, N = 1386) and with unilateral breast cancer (controls, N = 2045). Rate ratios (RR) and 95% confidence intervals (CI) were calculated to assess the relationship between BMI and risk of CBC stratified by menopausal and ER status. Positive associations with obesity and weight gain were limited to women who became postmenopausal following their first primary breast cancer. Among those with an ER‐negative first breast cancer, obesity (vs. normal weight) at first diagnosis was associated with an increased risk of CBC (RR = 1.9, 95% CI: 1.02, 3.4). Also, weight gain of ≥10 kg after first diagnosis was associated with an almost twofold increased risk of CBC (RR = 1.9, 95% CI: 0.99, 3.8). These results suggest that women with an ER‐negative first primary cancer who are obese at first primary diagnosis or who experience a large weight gain afterward may benefit from heightened surveillance. Future studies are needed to address the impact of weight loss interventions on risk of CBC.
- Published
- 2016