Tamoxifen and Second Breast Cancer: Epidemiology/Pathology
No involved investigator sites defined.
The BRITE Study (Breast Cancer Research Investigation of Treatment Effects) is a five-year, population-based nested case-control study, funded by the National Institutes of Health, to investigate the relationship between hormonal therapy for breast cancer and risk of contralateral breast cancer (CBC). The case group consists of 369 women diagnosed with a first primary invasive breast cancer, at ages 40 through 79, from 01/01/1990 to 12/31/2005, while residing in King, Pierce, Snohomish or Thurston counties, who subsequently developed invasive CBC while residing in the same geographic area. The control group consists of 734 similar women diagnosed with a first primary invasive breast cancer who had not developed CBC. Controls were randomly selected and matched to cases 2:1 on age, diagnosis date of the first cancer, and survival interval. The specific questions that were evaluated: • How does use of adjuvant tamoxifen therapy for a first primary breast cancer influence risk of developing ER– and ER+ CBC, and how does duration of use modify this riska • How does use of adjuvant tamoxifen therapy for a first primary breast cancer alter the expression of tumor markers involved in pathways leading to tamoxifen resistance in contralateral tumors, including ER subtypes, genes that control the cell cycle and apoptosis, and growth factors and their receptorsa • Does the expression of these tumor markers by first primary breast cancers or other patient characteristics predict which women have increased or decreased risks of developing CBC if they are treated with adjuvant tamoxifena • Among the women diagnosed with CBC, how does the use of tamoxifen alter the expression of these tumor markers in first compared to contralateral cancersa Data collection ended in 12/2007. Some analyses are complete and two papers were published in September 2009. The first paper, “Adjuvant Hormonal Therapy for Br east Cancer and Risk of Hormone Receptor-Specific Subtypes of Contralateral Breast Cancer,” documents that while tamoxifen therapy reduces risk of ER+ contralateral breast cancer it substantially increases risk of ER- contralateral breast cancer. The second paper, “Relationship Between Potentially Modifiable Lifestyle Factors and Risk of Second Primary Contralateral Breast Cancer Among Women Diagnosed with Estrogen Receptor-Posit ive Invasive Breast Cancer,” shows that obesity, alcohol use, and smoking are all positively related to contralateral breast cancer risk.
There are currently no biomarkers annotated for this protocol.
No datasets are currently associated with this protocol.