Breast cancer screening

• Mammography is the most widely used screening modality, with solid evidence of benefit for women aged 40 to 74 years

• Clinical breast examination and breast self-exam have also been evaluated but are of uncertain benefit

• Technologies such as ultrasound, magnetic resonance imaging, tomosynthesis, and molecular breast imaging are being evaluated, usually as adjuncts to mammography

American Cancer Society Guidelines for theEarly Detection of breast Cancer

• Yearly mammograms are recommended starting at age 40 and continuing for as long as a woman is in good health• Clinical breast exam (CBE) about every 3 years for women in their 20s

and 30s and every year for women 40 and over• Women should know how their breasts normally look and feel and

report any breast change promptly to their health care provider. Breast self-exam (BSE) is an option for women starting in their 20s

• Some women – should be screened with MRI in addition to mammograms

• The number of women who fall into this category is small: less than 2% of all the women in the US

Women at high risk

• This includes women with about a 20% or greater risk using risk assessment tools based mainly on

1. family history 2. women who had radiation therapy to the chest between the ages of

10 and 30 years3. women who either have or who are at high risk for mutations in

certain genes( BRCA1 and BRCA2)4. Certain genetic syndromes, such as Li-Fraumeni or Cowden syndrome

Harms

• Overdiagnosis and Resulting Treatment of Insignificant Cancers (follow-up of the long-term CNBSS and studies in the United States and Scandinavia found that at least 20% of screen-detected breast cancers are overdiagnosed) • Although the specific plan of recommended treatment is typically

tailored to individual tumor characteristics, at this time there is no reliable way to distinguish which cancer would never progress in an individual patient; therefore, some treatment is nearly always recommended

Harms

• Radiation-Induced Breast Cancer• The breast dose associated with a typical two-view mammogram is

approximately 0/4 mSv (seivert)and extremely unlikely to cause cancer. One Sv is equivalent to 200 mammograms. Latency is at least 8 years, and the increased risk is lifelong• Theoretically, annual mammograms in women aged 40 to 80 years

may cause up to one breast cancer per 1,000 women