Previous cancer and other breast conditions

Having breast cancer before or some breast conditions can increase your risk of breast cancer. For example, if you have, or have had, the following your risk may increase:

  • breast cancer, including ductal carcinoma in situ (DCIS)
  • lobular carcinoma in situ (LCIS)
  • atypical ductal hyperplasia which is when there’s an over-production of slightly abnormal breast cells
  • dense breast tissue, which means the breast is mostly made up of glandular and connective tissue with very little fatty tissue.

Radiotherapy to the chest at a young age

Radiotherapy to the chest to treat Hodgkin lymphoma can increase the risk of breast cancer.

Back to Potential causes of breast cancer

Age, lifestyle and risk

Your risk of developing breast cancer may increase with age, alcohol intake, being overweight and smoking.

Hormonal factors

Your exposure to the hormones oestrogen and progesterone can affect your risk of developing breast cancer.