It can be hard to understand your pathology results and you should ask your specialist or breast care nurse to explain anything you are unsure about. Here are some questions you might want to ask.
We recommend you refer to our booklet Understanding your pathology results for more information.
- What type of breast cancer do I have?
- Is it invasive or non-invasive or both?
- Can I have a copy of the pathology report?
- What size and grade is the breast cancer?
- Was the breast cancer tested for Ki67? If so, what was the result?
- Is there more than one area of breast cancer?
- Are there any signs of lympho-vascular invasion?
- Are there any breast cancer cells in the lymph nodes? If so, how many lymph nodes are affected?
- Is the breast cancer hormone receptor positive (ER+) or negative (ER-)?
- Is the breast cancer HER2 positive (HER2+)?
- Has all the breast cancer been removed as far as you can tell?
- Is a genomic assay test suitable for me? If so, what test will I have?
There are several types of breast cancer, all of which can be found at different stages of development and grow at different rates. Your pathology report will tell you which type of breast cancer you have.
Invasive primary breast cancer is breast cancer that has the potential to spread from the breast to other parts of the body.
Non-invasive breast cancers have not yet developed the ability to spread either within the breast or to another part of the body.
A pathology report describes the results of any tests done on tissue removed from the body. The information in these pathology reports helps your specialist team decide which treatments work best for you.
The size (usually in millimetres) and grade of your breast cancer will be included in your pathology results.
Some specialist teams measure a protein called Ki67 as well as grade. The higher the levels, the faster the cells are dividing and growing.
Ki67 is not usually included in pathology results. If it is, the report will say what percentage of the breast cancer cells test positive for Ki67. Less than 10% is considered low, 10–20% is medium and more than 20% is high. The higher the score, the faster the cells are dividing and growing.
Sometimes there may be more than one area of breast cancer. In this case each area is measured.
The breast contains networks of lymph vessels and blood vessels that connect the breast to the rest of the body. If breast cancer cells invade (break through) the walls of these vessels, it’s called lympho-vascular invasion. This increases the chances of the breast cancer spreading to somewhere else in the body.
If you have invasive breast cancer, your specialist team will usually want to check if any of the lymph nodes under the arm contain cancer cells.
All invasive breast cancers are tested for oestrogen receptors using tissue from a biopsy or after surgery. The hormone oestrogen can stimulate some breast cancers to grow.
Some breast cancer cells have a higher than normal level of a protein called HER2 on their surface, which stimulates them to grow.
Your pathology report will say how close the cancer cells are to the edges of the whole area of tissue that was removed. This is called the surgical margin. It’s important that the cancer is removed with an area of healthy tissue around it to make sure no cancer cells have been left behind.
- negative (clear) margins mean no cancer cells were seen at the outer edge of the tissue removed.
- positive margins mean the cancer cells are very close to or reach the edge of the tissue.
Your pathology report is likely to give the distance of the cancer to all the margins around. Words you may see in your report include superior (top), inferior (bottom), medial (towards the middle), lateral (towards the edge), superficial/anterior (front) and posterior/deep (back). Different hospitals will have their own guidelines as to how large the margin of clear, healthy tissue should be, but it’s usually about a minimum of 1mm around the cancer.
These tests look at groups of genes found in the breast cancer. They help identify who is most likely to benefit from chemotherapy and how likely the cancer is to return (recurrence). If any of these tests could be of benefit to you and are available, your specialist team should discuss this with you.