What Is Breast Cancer?

Receiving a breast cancer diagnosis can feel overwhelming, and it is completely normal to have questions. This video explains what breast cancer is, where it starts in the body, and the different forms it can take. Cancer develops when cells in the body begin to grow, and divide in an uncontrolled way. Breast cancer starts in the breast tissue. Over time, these abnormal cells can form a lump or tumour. Not all lumps are cancer, but any new or unusual changes should always be checked by a doctor. To understand breast cancer, it helps to know a little about breast anatomy. The breast contains fatty tissue; milk-producing glands called lobules; and thin tubes called ducts that carry milk to the nipple. Breast cancer most commonly begins in the cells lining the ducts - though it can also start in the lobules. Breast cancer is the most common cancer in the UK and, each year, thousands of people are diagnosed. The good news is that survival rates have improved significantly over recent decades, thanks to earlier detection and better treatments. Most people diagnosed with breast cancer today will survive their disease. Breast cancer is often described as either "in situ", or "invasive". These terms describe whether the cancer cells have stayed in one place or have started to spread beyond the ducts or lobules into the surrounding breast tissue. You will only know this information with the results of a biopsy - it is not possible to tell just from scans or mammograms. Your clinical team will explain which type you have, as this affects your treatment options. "In situ" means the cancer cells are contained within the ducts or lobules where they started. They have not spread into nearby breast tissue. The most common type is "Ductal Carcinoma In Situ", sometimes called DCIS. It has three catagories, low, intermediate or high grade. This grade is different from the grades of invasive cancer. In situ disease is not life-threatening, but it is usually treated to prevent it becoming invasive. There is some evidence that older patients with low grade DCIS can avoid treatment, but most patients will have DCIS removed with an operation. There are several different subtypes of breast cancer, which depend on factors such as: the cancers sensitivity to female hormones oestrogen and progesterone; and some other specialised tests done on the biopsy. These are performed by testing the cancer cells in the biopsy taken in a laboratory. The initial results take about 48 hours to come back but the final results of the subtype take 5 to 7 days. Other videos in this series explain each subtype in more detail. Although breast cancer is far more common in women; men can develop it too. Men have a small amount of breast tissue, and cancer can form there in the same way. Being diagnosed with breast cancer does not mean facing it alone. You will have a specialist team to guide you through diagnosis, treatment, and recovery.