How is Breast Cancer Detected?

Screening refers to tests and exams used to find a disease, like cancer, in patients who don’t have any symptoms. The goal is to diagnose cancer before it starts to cause symptoms, because the earlier breast cancer is found, the more likely treatment will work effectively.

The size of a particular breast cancer and how widely it has spread are the most important factors in predicting the outlook for a patient. Most doctors feel that tests for finding breast cancer early save many thousands of lives each year.

Here are the American Cancer Society recommended guidelines for finding breast cancer early in women without symptoms:

Breast Self-Exam (BSE)

Breast self-exams are crucial for day-to-day breast cancer prevention. Starting in their 20s, women should be taught how to look and feel for anomalies in their own breasts. Women should report any changes in how their breasts look or feel to a health expert right away. Changes may include a lump or swelling, skin irritation or dimpling, nipple pain or the nipple turning inward, redness or scaliness of the nipple or breast skin, or discharge other than breast milk. But remember that most of these changes are not indicative of breast cancer.

Clinical Breast Exam (CBE)

Women in their 20s and 30s should have a clinical breast exam (CBE) as part of a regular exam by a health expert at least every three years. After age 40, women should have a breast exam by a health expert every year. It might be a good idea to have the CBE shortly before a mammogram. Women can use the exam to learn how their own breasts look and feel.


Women over the age of 40 should have a mammogram screening every year and should continue to do so for as long as they are in good health. While mammograms can miss some cancers, they are still a very good way to find breast cancer.

Magnetic Resonance Imaging (MRI)

Women at high risk (25% or more lifetime risk) should get an MRI and a mammogram every year. For women at a moderately increased risk, the benefits and limitations of adding an MRI to their annual mammogram should be discussed with their doctors. Yearly MRI screenings are not recommended for women whose lifetime risk of breast cancer is less than 15%.