Tests and exams used to find a disease, like cancer, in people who do not have any symptoms are called screening tests. Screening exams, such as mammograms, find cancers before they start to cause symptoms. This is called early detection. Cancers that are found early – when they’re small and haven’t spread – are easier to treat and have better outcomes

Breast Cancer Prevention and Early Detection has more details about the American Cancer Society guidelines for the early detection of breast cancer.

Why is it important to find breast cancer early?

The earlier breast cancer is found, the better the chances that treatment will work. Breast cancers that are found because they can be felt tend to be larger and are more likely to have already spread outside the breast. But screening exams can often find breast cancers when they are small and still confined to the breast. The size of a breast cancer and how far it has spread are some of the most important factors in predicting the outlook (prognosis) of a woman with this disease.

Most doctors feel that early detection tests for breast cancer save thousands of lives each year. Many more lives probably could be saved if even more women and their health care providers took advantage of these tests.