Cancer control by family history.

Family history can be used to identify persons at high cancer risk and to target appropriate preventive and therapeutic measures. First-degree female relatives of women with breast cancer (n = 600) are at increased risk for breast cancer (RR: 1.7.95% CI: 1.4-1.9). First-degree relatives of colorectal cancer patients (n = 184) are at increased risk for colorectal cancer (RR: 1.8.95% CI: 1.4-2.3). Families with hereditary cancer syndromes are identified. The family history approach can be used in every part of the world, and it should become a part of future cancer control activities.