Influence of Radiotherapy and Tamoxifen on Contralateral Cancer Risk in Women with Hereditary Breast Cancer
Abstract
Women with breast cancer arising as a consequence of germline mutations in BRCA1 or BRCA2 are at significant risk of contralateral breast cancer (CBC). Examination of factors influencing contralateral risk will provide insight into prevention strategies for unaffected women with BRCA mutations. To evaluate CBC risk factors, the funded study was designed to assess the impact of tamoxifen and radiotherapy on CBC risk. Records from a total of 874 Ashkenazi women with breast cancer diagnosed between 1990 and 1996 were reviewed to expand the initial cohort of 305 women treated between 1980 and 1990. Changes in medical record storage and HIPAA privacy regulations prevented the gathering of required basic clinical and/or follow-up information for 75% of patients diagnosed between 1990 and 1992, and for approximately 20% of patients diagnosed between 1992 and 1996. The loss of the patients from the data set introduced a possible survival bias, and thus alternative methods of addressing the study goals were sought. Specifically, concatenation of the original 1980-1990 data set with a similar ascertainment from another institution was performed, suggesting a 53% contralateral risk reduction with adjuvant tamoxifen, and 103 clinically ascertained patients were analyzed. The clinical ascertainment did not support a benefit from tamoxifen.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2004
- Accession Number
- ADA430045
Entities
People
- Mark E. Robson
Organizations
- Memorial Sloan Kettering Cancer Center