Genetic/Familial high-risk assessment: breast and ... [J Natl Compr Canc Netw. 2010] - PubMed result

Abstract

Overview
All cancers develop as a result of mutations in certain genes, such as those involved in the regulation of cell growth and/or DNA repair,(1,2) but not all of these mutations are inherited from a parent. For example, sporadic mutations can occur in somatic/tumor cells only, and de novo mutations can occur for the first time in a germ cell (i.e., egg or sperm) or in the fertilized egg itself during early embryogenesis. However, family studies have long documented an increased risk for several forms of cancer among first-degree (i.e., parents, siblings, and children) and second-degree relatives (i.e., grandparents, aunts or uncles, grandchildren, and nieces or nephews) of affected individuals. These individuals may have an increased susceptibility to cancer as the result of 1 or more gene mutations present in parental germline cells; cancers developing in these individuals may be classified as hereditary or familial cancers. Hereditary cancers are often characterized by mutations associated with a high probability of cancer development (i.e., a high penetrance genotype), vertical transmission through either mother or father, and an association with other types of tumors.(3,4) They often have an early age of onset and exhibit an autosomal dominant inheritance pattern (i.e., occur when the individual has a mutation in only 1 copy of a gene). Familial cancers share only some features of hereditary cancers. For example, although familial breast cancers occur in a given family more frequently than in the general population, they generally do not exhibit the inheritance patterns or onset age consistent.