Importance of family history and indications for genetic testing.

Family history is an important cancer risk assessment tool, and it is easy to use. The family history is integral in identifying an individual's risk for primary cancer and assists in the assessment of risk for a second primary cancer. For oncology providers, the critical family history is defined as including first- and second-degree family history, maternal and paternal history, type of primary cancer, and age at diagnosis and ethnicity. Family history should be taken at diagnosis and updated periodically. Despite the importance of family history to patient care, there are significant barriers to taking a family history. We review the impact of collecting complete family history data with respect to calculation of cancer risk, recommendations for screening, and prevention strategies and referral for genetic testing.