Inherited breast cancer

Abstract

Breast cancer is the most common cancer among women in Western countries, with about 180,000 new cases and 40,000 deaths occurring annually in the United States. Epidemiologic factors consistently associated with breast cancer risk include a family history of breast cancer, breast biopsy features, and hormonal risk factors such as age at menarche, parity, and age at first live birth. After female gender and age, family history of breast cancer is the most significant risk factor. In a meta-analysis of family history of breast cancer as a risk factor, the relative risk ranged from 1.5 for a second-degree relative to 3.6 for a mother and sister with breast cancer.1 Relative risks are significantly influenced by the degree of relationship of affected relatives and their age of breast cancer onset, with closer degrees of relationship and younger age of onset conveying higher risks. An analysis of family history as a risk factor using data from the Swedish Family-Cancer Database showed a populationattributable fraction of about 11%.2 © 2007 Springer Science+Business Media, LLC.