How is breast cancer diagnosed?
With the use of screening mammograms, more and more breast cancers are being detected at an early and curable stage. Cancer screening refers to the performance of test to look for early evidence of cancer in people of average risk. The term does not apply to those at higher risk, such as those with a positive family history of cancer. Mammograms and breast examinations are the most important screening tests for breast cancer. Mammograms can identify many tumors that are too small to be felt by the patient; up to 90% of breast cancers can be found by mammography.
Guidelines for mammography
Experts are not in full agreement about when a woman should begin having mammograms. The American Cancer Society (ACS) recommends a first mammogram for all women by age 40, and annual mammograms for women 40 and older. The U.S. Preventive Services Task Force (USPSTF) recommends against routine mammography for women before 50 years of age. However, women at high risk for breast cancer may need to begin having mammograms earlier in life, and may undergo screening recommended for their individual situation.
Other breast cancer detection methods
One concern about the use of mammography in younger women is that mammograms may not as efficiently detect breast cancer in women with dense breast tissue, which is more likely to be found in young women. The use of ultrasound combined with mammography is often recommended in these cases. Ultrasound is used to supplement traditional mammography in numerous uncertain or difficult cases. In some situations, magnetic resonance imaging (MRI) is also used to help detect breast cancers.
Should I do a breast self exam?
Neither the ACS nor the USPSTF recommend regular self-examination of the breasts in their guidelines. The ACS policy states that breast self-exam is optional, while the USPSTF guidelines say that doctors should not teach women to do breast self-examination. However, the ACS does recommend a clinical breast exam (CBE) by a health care professional around every three years for women in their 20s and 30s and every year for women 40 years of age and over.
The definitive diagnosis
Although imaging studies and examinations can reveal lumps or suspicious areas in the breast tissue, the definitive diagnosis of breast cancer involves sampling cells or tissue from the suspicious area and confirming the presence of cancer on microscopic examination. Tests used to look at breast samples include different kinds of breast biopsy and fine needle aspiration of the breast.
Medically reviewed by Jay B. Zatzkin, MD; American Board of Internal Medicine with subspecialty in Medical Oncology
Cancer.org. Cancer Screening Guidelines.
Cancer.org. Breast Cancer Prevention.
U.S. Preventitive Task Force. Screening for Breast Cancer.
Cancer.gov. Breast Cancer.