Epidemiology and risk factors.

HBC is common, accounting for approximately 9% of the total breast cancer burden. Given 142,000 cases of breast cancer expected to occur in 1989, this would represent 12,780 cases of HBC patients. Soberingly, each patient represents a family with a variable number of inordinately high risk patients. HBC's natural history is distinctive and enables the identification of at risk patients who can benefit from highly targeted surveillance/management strategies. High priority must be given to development of biomarkers that will one day be found to have acceptable sensitivity and specificity to genotype status. Thus, we would then be able to tell which of the first-degree relatives of affected members have inherited the deleterious gene. This would result in a significant saving of time and money that would otherwise be expended through intensive surveillance strategies. We need cost-benefit research to induce third party carriers to defray expenses for surveillance. Finally, priority attention must be given to biomolecular research for identification of markers of acceptable sensitivity and specificity to the cancer-prone genotype. Eventual cloning of the deleterious gene(s) could lead to knowledge about its chemical and physiologic products, thereby enabling anticancer pharmacologic research. The reward could then be improved control and even prevention of breast cancer, and possibly of the associated cancers in heterogenous forms of this disease.