A prospective study of breast cancer risk in relatives of BRCA1/BRCA2 mutation carriers

• Published in: Journal of medical genetics Vol. 44; no. 8; p. e89
• Main Authors: Rowan, Erica, Poll, Aletta, Narod, Steven A
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd 01.08.2007; BMJ Publishing Group LTD; BMJ Group
• Subjects: Adult; Aged; BRCA1; BRCA2; Breast cancer; Breast Neoplasms - epidemiology; Breast Neoplasms - genetics; Correspondence; Family; Female; Genes, BRCA1; Genes, BRCA2; Genetic Carrier Screening; Genetic Testing; Health risk assessment; hereditary breast cancer; Heterozygote; Humans; Mammography; Middle Aged; Mutation; mutation negative risk; Ontario - epidemiology; Patient Selection; Risk; Studies; Ontario Canada
• ISSN: 0022-2593; 1468-6244

Smith et al reported that 24% of 118 relatives with breast cancer or ovarian cancer cases in 277 families with a BRCA mutation were phenocopies, and they estimated the risk of breast cancer in mutation-negative women to be five times greater than expected. 6 Gronwald et al studied unselected cases of breast cancer in Poland, 7 and found that only one of 17 affected sisters was a phenocopy, and that one of 72 non-carrier relatives had developed breast cancer. The subject's mother was also diagnosed with bilateral breast cancer (at the ages of 48 and 59); however, she was found to be mutation-negative. [...]owing to the presence of a case of bilateral breast cancer in the family, which was not accounted for by the familial mutation, this subject was considered to be at greater risk, despite the negative result.