Understand your pathology report

It’s important to understand what type of breast cancer you have (its ‘pathology’ or biology). The pathology report helps your doctor:

• understand the type of cancer you have 
• make decisions about the best treatment for you.

Pathology reports can be confusing and sometimes doctors don't discuss their content. We explain what the different terms mean and provide more information.

Your surgeon, oncologist or breast care nurse can explain your results and reports so you understand your type of breast cancer and the treatments they recommend.

Types of pathology reports

When you have a biopsy or surgery, breast cells, tissue or lymph nodes may be removed for testing. A specialist (a pathologist) analyses each sample of tissue and writes a pathology report.

The 2 main types of pathology reports are:

• an initial biopsy report – this aims to confirm if a change in your breast is cancer or not. If it is, the report will show early ('provisional') information on the type and how fast it is growing.
• a breast cancer pathology report – this is provided after surgery. It confirms the initial biopsy report and has more specific information about your breast cancer cell.

What is in a breast cancer pathology report

Your post-surgery pathology report contains medical information such as:

• what type of cancer it is
• how big the cancer is
• how fast the cells are growing
• whether cancer is present in the lymph nodes in your armpit
• whether there are any hormone or HER2 receptors on or inside the cancer.

We explain the main contents of the report. Most of the detail explains what the pathologist found when they looked at the tissue under a microscope.

Type of tissue

The sort of tissue the surgeon provided, for example, tissue from a core biopsy, a mastectomy, or lymph nodes.

Location of your breast cancer

Where the cancer is. For early breast cancer, this refers to the breast and may refer to lymph nodes. For metastatic breast cancer, this may include the part of the body the breast cancer has spread to.

Type of cancer

There are many different types of breast cancer including invasive and non-invasive. Knowing the type and subtype helps the doctor understand the likely outcome. See Types and subtypes of breast cancer.

Grade

Cancer cells are given a grade that tells doctors:

• how different they are from normal breast cells
• how fast the cells are growing.

The range is usually from 1 (low-grade or slow-growing cells) to 3 (high-grade with faster growing cells).

Anatomic stage

The anatomical stage shows:

• the size of the breast cancer
• the parts of the body that are affected.

The system is usually numbered from 0 to 4. If you have any body scans done as part of your breast cancer imaging, the results will provide information on the stage of the cancer.

Note: pathology reports refer to 2 'stages' - anatomic stage and the more detailed prognostic stage. We explain more at Stages of breast cancer.

Surgical margin

When a surgeon removes a breast cancer tumour, they also remove some of the healthy-looking tissue around it. This aims to ensure that all of the cancer has been removed.
Surgical margin is clear: the pathology report shows there are no cancer cells left in the healthy looking tissue around the cancer.
Surgical margin is not clear: if the margin is not clear, it still has some abnormal cells. Your doctor may recommend further surgery.

Lymph nodes

You may have lymph nodes removed from your breast or armpit (axilla) during breast cancer surgery. If cancer is found in the lymph nodes, the report will include:

• how many lymph nodes were removed
• how many lymph nodes contain cancer cells (‘positive nodes’)
• their size
• whether the cancer extended into the surrounding tissue.

This is one of the factors that affects whether chemotherapy is recommended for you. Read about lymph nodes.

Hormone receptors

Abnormal cells may have receptors for the hormones oestrogen (ER) or progesterone (PR) or both.
If these receptors are present on your breast cancer, it is ‘hormone receptor positive’. The report shows this as ER+ and/or PR+.

Hormone receptor positive breast cancers are divided into two categories:

• Luminal A: these tumours are oestrogen receptor positive (ER+) and are often low grade with slow tumour growth.
• Luminal B: these tumours are also ER+ but with quicker tumour growth than Luminal A.

HER2 status

HER2 is a protein on a cell that affects the growth of the breast cancer. The report shows if there are a lot of HER2 receptors on your breast cancer cells. If there are, your cancer is HER2 positive. Treatment such as trastuzumab will be recommended for you.

Ki-67

Ki-67 is a protein in cells that increases when cells are dividing. Sometimes the pathology report shows the percentage of cells containing Ki-67. The more positive cells there are, the more quickly they are dividing and forming new cells. Luminal B tumours have higher Ki-67 than Luminal A. The definition of 'high' varies from lab to lab but a ki67 above 15-20% is classed as high.

Summary and diagnosis

This is a short summary of the whole report and a specific diagnosis. For example, it may say 'Invasive ductal carcinoma, grade 2, ER+, PR+, HER2 negative, 17mm diameter, clear surgical margins, no lymph node involvement'.

Keep records of your test results

You might find it helpful to keep a file of your test results and reports. You can access them easily if you see doctors in different treatment centres.

We encourage you to ask your doctor for a copy of your pathology report and other test results so you:

• understand your diagnosis better
• can ask questions about your specific diagnosis
• have a record of the details, in case you need them later on.

My Health Record also helps you keep all your health information in one place. It is a safe online record provided by the Australian Government.

You and your health professionals can add information such as:

• medications you are taking
• results from tests and scans
• health conditions you have been diagnosed with
• any allergies you have
• your Medicare information.

Access My Health Record from any computer or mobile device with an internet connection.

What happens to breast tissue used for testing

After surgery, some of your breast cancer tissue is kept in paraffin wax blocks. These are used to prepare slides for the pathologist to examine under a microscope.

They can do multiple tests using the same paraffin blocks, even many years after your diagnosis.

The laboratory that tests your first tissue sample keeps these blocks, labelled with your details. They may store them on-site or in their off-site facility for 10 years or more after your original surgery.

If doctors need to do further testing, they can access your paraffin block, using the information in your pathology report.