There are 4 stages in breast cancer. These are:

Ductal ectasia is the dilation and hardening of the milk duct. Dilation of the milk ducts is more commonly observed in women aged 40 and 50.

The breasts are composed of tissue made up of lobules that produce milk, ducts that transport the milk to the nipple, and supporting tissue such as fatty tissue and fibrous connective tissue. The lobules and milk ducts form the structure of the breast and are responsible for milk production. Fatty and fibrous tissues give shape to the breast. The combination of fat and fibrous tissue is referred to as the "glandular" structure.

Breast cancer is the most common cancer among women and the leading cause of cancer-related deaths. It accounts for 24% of all female cancers and 15.5% of cancer deaths. It is reported that 1 in 8 women will be diagnosed with breast cancer at some point in their lives. Rarely, breast cancer is also seen in men, with 1 man diagnosed for every 100 women. The incidence of breast cancer has been found to increase every year.

The high prevalence of breast cancer, its increasing frequency, the possibility of treating it in its early stages, and the ability to diagnose it at an early stage under current conditions all increase the importance of screening methods for breast cancer.