Breast cancer family history as a risk factor for early onset breast cancer

Abstract

Since full breast cancer screening is not generally recommended for young women, it is important to identify individuals who are at higher risk for early onset breast cancer. We investigated the relationship between age of onset of breast cancer in 328 probands (consecutively ascertained patients from our oncology clinic) and breast cancer incidence and age of onset in their female relatives. We found that a family history of early onset breast cancer was associated with higher risk of early onset breast cancer. A family history of early onset breast cancer occurred more frequently among young (<40) breast cancer probands than among older (≥40) breast cancer probands (p<0.001; OR = 23). This relationship was particularly evident when the analysis was restricted to the hereditary breast cancer probands (p<0.001; OR = 44). We also observed a positive family history of breast cancer (any age) more frequently in young breast cancer probands than in older breast cancer probands (p<0.001; OR = 2.8). These observations have important pragmatic implications for surveillance. We recommend intense surveillance for breast cancer, initiated earlier, for women with close relatives diagnosed with early onset breast cancer. © 1988 Kluwer Academic Publishers.