The purpose of breast screening is to detect breast cancer as early as possible because it enables the best chance of being cured.

Breast cancer screening involves examining people for signs that may indicate that cancer is developing. The screening uses a test called a mammogram, which involves taking an X-ray of the breast. 

The screening can help detect breast cancer early because any lesions are too small to be noticed. These very small cancers are usually easier to treat than larger ones. 

Younger women’s mammograms are harder to read because they have denser breast tissue. So the pattern on the mammogram is not so easy to see. There is little evidence that regular mammograms for women under screening age reduce breast cancer deaths.

Breast cancers found during screening are usually in an early stage. Early-stage breast cancer is often easier to treat, may require less treatment, and is more likely to be cured. Nearly all women diagnosed with breast cancer at the earliest possible stage live at least 5 years after diagnosis and are likely to be cured.