Description of the Evidence
Table 1. Risk of Breast Cancer Diagnosisa
|Current Age (in Years)||Risk in Next 10 Years||Lifetime Risk of a Breast Cancer Diagnosis|
|a Adapted from Altekruse et al.|
|30||1 in 250||1 in 8|
|40||1 in 71||1 in 9|
|50||1 in 42||1 in 9|
|60||1 in 29||1 in 11|
|70||1 in 27||1 in 15|
The incidence of breast cancer increases with a woman's age. As shown in Table 1, a 60-year-old woman has a higher risk of being diagnosed with breast cancer in the next 10 years than does a 40-year-old woman.
The cumulative lifetime incidence decreases with advancing age because the longer a woman lives without a breast cancer diagnosis, the lower her lifetime risk compared to a younger woman who might develop breast cancer at a younger or older age. The commonly quoted risk of one in eight women who will be diagnosed with breast cancer is based on lifetime risk of a diagnosis (not death) starting from birth and does not account for the woman's current age.
Breast cancer mortality increases with age. For a 40-year-old woman without a breast cancer diagnosis, the chance of dying from breast cancer within the next 10 years is extremely small, but for a woman older than 65, it is about 1%. For a woman older than 70, the risk of dying of breast cancer is even higher, but the risk of dying of any cause is higher yet.
Personal history of breast cancer
Women with a personal history of invasive breast cancer, DCIS, or lobular carcinomain situ also have an increased risk of being diagnosed with a new primary breast cancer. Recommendations for subsequent mammograms vary, but evidence for various strategies is scant.
Prior radiation therapy
Women treated with thoracic radiation before the age of 30 years have a 1% annual risk of breast cancer, starting 8 years after the irradiation and for the rest of their lives.[7,8] Annual screening with magnetic resonance imaging has been proposed in such women, beginning 8 years after treatment or by age 25 years, whichever is later. Because this population is small, there are no studies to confirm the benefit of this recommendation.