Not all breast cancers are the same

If you have never been affected by breast cancer, you might think that you get it and you are treated and that's the end of it. I certainly never knew that there were different types or that your treatment differed depending on what type you are diagnosed with. A breast cancer's type is determined by the specific cells in the breast that become cancer. Some cancers are invasive - meaning they have escaped the breast duct or lobule and have spread to the nearby breast tissue. Some are 'in situ' meaning they are still within the duct or lobule.
Below I explain what the more commonly found types are.

Triple Positive

Triple positive breast cancer is when you are positive (after tests have been done at the time of biopsy) for both hormones (oestrogen and progesterone) and a protein gene called HER2 (human epidermal growth factor receptor 2). This protein is responsible for the growth of cancer cells. This all means that your cancer is driven by both hormones, and where you are HER2 positive, it means that you have an extra copy of this gene which in turn means your cancer will grow faster than those cancers that are HER2 negative.
About 1 in every 5 cancers are HER2 positive and whilst it certainly sounds scary to have what is commonly referred to as an 'aggressive type' of cancer, on the flip side, there are many targeted therapies that work well in fighting this type.

Triple Negative

Triple-negative breast cancer (TNBC) accounts for about 10-15% of all breast cancers. They are the opposite of triple positive, in that they are not driven by either of the main female hormones, nor do they make any or much of the HER2 protein. In other words, they test negative for these three tests. Unlike cancers with an over expression of HER2, there are not any targeted therapies that can be used to treat this type. Nor any of the hormone treatments that are commonly used. Treatment usually consists of chemotherapy, surgery and radiotherapy.

DCIS (Ductal Carcinoma In Situ)

DCIS is often referred to as stage 0 cancer. It is where cancer cells have grown within the milk ducts of a breast, but that hasn’t spread into the breast tissue around it. It therefore can’t spread (metastasize) beyond the breast to other parts of the body. DCIS can sometimes become an invasive cancer though, which means the cancer has spread out of the duct into nearby tissue. Because there is no way of ever knowing when (if ever) this would happen, DCIS is almost always treated. The treatment is usually surgery to remove the area, followed by radiation. Or a mastectomy and no radiation. If the DCIS is hormonally driven, then hormone treatments can also be given