Association of breast cancer with MRI background parenchymal enhancement: the IMAGINE case-control study.

BACKGROUND: Background parenchymal enhancement (BPE) on breast magnetic resonance imaging (MRI) may be associated with breast cancer risk, but previous studies of the association are equivocal and limited by incomplete blinding of BPE assessment. In this study, we evaluated the association between BPE and breast cancer based on fully blinded assessments of BPE in the unaffected breast. METHODS: The Imaging and Epidemiology (IMAGINE) study is a multicenter breast cancer case-control study of women receiving diagnostic, screening, or follow-up breast MRI, recruited from three comprehensive cancer centers in the USA. Cases had a first diagnosis of unilateral breast cancer and controls had no history of or current breast cancer. A single board-certified breast radiologist with 12 years' experience, blinded to case-control status and clinical information, assessed the unaffected breast for BPE without view of the affected breast of cases (or the corresponding breast laterality of controls). The association between BPE and breast cancer was estimated by multivariable logistic regression separately for premenopausal and postmenopausal women. RESULTS: The analytic dataset included 835 cases and 963 controls. Adjusting for fibroglandular tissue (breast density), age, race/ethnicity, BMI, parity, family history of breast cancer, BRCA1/BRCA2 mutations, and other confounders, moderate/marked BPE (vs minimal/mild BPE) was associated with breast cancer among premenopausal women [odds ratio (OR) 1.49, 95% CI 1.05-2.11; p = 0.02]. Among postmenopausal women, mild/moderate/marked vs minimal BPE had a similar, but statistically non-significant, association with breast cancer (OR 1.45, 95% CI 0.92-2.27; p = 0.1). CONCLUSIONS: BPE is associated with breast cancer in premenopausal women, and possibly postmenopausal women, after adjustment for breast density and confounders. Our results suggest that BPE should be evaluated alongside breast density for inclusion in models predicting breast cancer risk.

Utilization of Complementary Alternative Medicine, Diet, and Exercise Among Women at High Risk for Developing Breast Cancer.

Background: Women diagnosed as having a high risk for breast cancer (HR-BC) often seek different health behaviors (HBs) such as complementary and alternative medicine (CAM), diet, and exercise to improve their health and cancer outcome. Methods: Women already enrolled in a multimodality screening study for patients at HR-BC (gene mutation carrier or >20% cumulative lifetime risk) were given a questionnaire to evaluate their use of CAM therapies, diet, and exercise before and after a diagnosis of HR-BC. Patients were also asked to complete the Short-Form 36, State-Trait Anxiety Inventory, and Beck Depression Inventory. Results: A total of 134 (67%) subjects completed the survey from the original cohort. General characteristics included a median age of 46 years (range = 24-73 years), majority were White (91%), BRCA1/2 gene mutation carrier (49%), and prior diagnosis of breast and/or ovarian cancer (30%). Almost all of the patients reported a lifetime prevalence of any HB (97%) and CAM utilization (91%). Subjects also had a high lifetime utilization of exercise (83%), herbs and supplements(72%), and diet programs (58%). All of these HBs declined in utilization after diagnosis of HR-BC by as much as 30%. After diagnosis of a HR-BC, a personal history of breast and/or ovarian cancer was significantly correlated with increased use of CAM (odds ratio [OR] = 5.9, P < .01), herbs and supplements (OR = 4.3, P < .01), and diet program (OR = 4.4, P < .01) in multivariate analysis. Conclusions: HBs such as CAM, diet, and exercise are highly prevalent among women with HR-BC, and the utilization of HB decreases significantly after diagnosis of HR-BC.