Breast cancer is when abnormal cells in the breast begin to grow and divide in an uncontrolled way and eventually form a growth (tumour).
Breast cancer most commonly starts in the cells that line the milk ducts of the breast. It is the most common cancer in the UK. It mainly affects women, but men can get it too.
Where breast cancer starts
Breast cancer can start in different parts of the breast. Most commonly it starts in the cells that line the ducts of the breast. This is invasive breast cancer or invasive ductal carcinoma. Invasive means the cancer cells have spread outside the ducts where they started and into the surrounding breast tissue.
They can also start in the lobules of the breast. This means that the cancer has spread outside the lobules and into the surrounding breast tissue. This is invasive lobular breast cancer.
There are also other rarer types of breast cancer.
Who gets it?
Breast cancer is more common in women than men. Around 55,500 women and around 370 men are diagnosed in the UK each year.
1 in 7 women in the UK develop breast cancer during their lifetime. It is more common in older women.
Breast cancer risk can be affected by age, family history and lifestyle factors. This includes obesity and smoking.
How common it is?
Breast cancer is the most common cancer in the UK. Around 55,900 people are diagnosed with breast cancer every year in the UK. That is more than 150 people a day.
15 out of 100 (15%) newly diagnosed cancers in the UK are breast cancer.
If you have any concerns about breasts, please see your GP/Doctor.
Self-examination guides can be found here from www.breastcancernow.org