Review: breast cancer is associated with a family history of the disease in first degree relatives
QUESTION: In women with a family history of breast cancer, how does the pattern of breast cancer in first degree relatives affect the risk of developing the disease?
Data sources
Studies were identified by searching computerised literature databases, reviewing bibliographies of review articles, and contacting experts in the field.
Study selection
Studies were selected if they were cohort or nested case control studies, included ≥100 women with incident invasive breast cancer, and information about reproductive or hormonal factors was sought on each woman.
Data extraction
Principal investigators of the included studies were contacted for data on each woman regarding whether any of her first degree female relatives (mother, sisters, or daughters) had been diagnosed with breast cancer and, if so, their age when the diagnosis was made. Data were also collected on the numbers of sisters and daughters of each woman, and the ages of each unaffected first degree female relative.
Main results
52 published and 2 unpublished studies included 58 209 women with breast cancer (median age 52 …
