Pathology Report Results
Updated September 27, 2010
The results in your pathology report help you and your treatment team understand how aggressive the cancer is and whether it has traveled—or is likely to travel—outside its original location.
What it is: Describes whether the cancer cells can travel beyond the area where they first started growing.
Possible results: Invasive, noninvasive (also called in situ) or mixed.
What the results mean: Invasive means the cells can travel into surrounding healthy tissue and the lymph nodes. Noninvasive means the cancer stays put in its original location and does not travel.
Mixed means there are areas of invasive and noninvasive cancer.
What it is: Describes what the cells’ structure and growth patterns look like under the microscope.
Possible results: Ductal carcinoma (starts in the breast’s milk-carrying channels, called ducts) or lobular carcinoma (starts in the lobules, or milk-producing sacs). There are some rare subtypes of ductal and lobular carcinoma, as well as other types of cancer that start in other parts of the breast; see your treatment team for more information.
What the results mean: In some cases, cell type can affect treatment decisions.
What it is: Measures how large an invasive tumor is at its widest point.
Possible results: Can range from 1 millimeter (mm) or less across to 5 centimeters or more (about 2 inches).
What the results mean: Size helps determine the stage of the cancer.
What it is: A “score” of how abnormally the cancer cells behave and look when compared with normal breast cells.
Possible results: 1 (low grade or well-differentiated), 2 (moderate grade or moderately differentiated), 3 (high grade or poorly differentiated).
What the results mean: The higher the grade, the faster the cells grow and the less they look like healthy cells.
What it is: Tells whether the cancer cells are found in the blood vessels or lymph-carrying channels of the breast.
Possible results: Present or absent.
What the results mean: The blood vessels and lymph channels in the breast are part of a network that goes throughout the whole body. Having cancer cells there increases the risk of the cancer traveling outside the breast or coming back in the future.
What it is: Explains whether a complete margin, or surrounding rim of healthy tissue, was removed along with the breast cancer during surgery.
Possible results: Negative (or clean), positive or close.
What the results mean: Having negative or clean margins means that no cancer cells can be seen at the outer edge of the tissue that was removed. This is the best way to ensure that all cancer was taken out. Positive means the cancer cells come right out to the edge of the tissue; some cancer may have been left behind. Close means that the cancer cells are close to the edge of the tissue, but not right at the edge. Cases of positive or close margins may require more surgery.
A note on results: Hospitals define clean margins differently. See your treatment team for more information.
What it is: Tells whether cancer cells were found in the underarm lymph nodes.
Possible results: Negative (no cancer found, nodes are clear) or positive (cancer found). If positive, the report will tell you how many lymph nodes have cancer and how much cancer is in each node—ranging from a few tiny cells to many cells that can be seen easily.
What the results mean: Having cancer in the lymph nodes increases the risk of the cancer traveling beyond the breast.
What it is: Describes the cancer based on size and lymph node status.
Possible results: Stage I, II, III or IV. Stages I, II and III may be divided into more categories (IA or IB, IIA or IIB; IIIA, IIIB or IIIC).
What the results mean: The higher the stage, the more advanced the cancer is. Stage I means the tumor is smaller than 2 cm with either clear lymph nodes or a very tiny number of cancerous cells in the lymph nodes, while Stage IV means the cancer has traveled to other areas of the body. In Stages II and III, the tumor is larger than 2 cm and the lymph nodes may or may not have cancer.
What it is: Tells whether the cancer cells have receptors for growth signals coming from the hormones estrogen and progesterone. Receptors are special proteins that receive messages from these hormones in the bloodstream telling the cells to grow.
Possible results: Positive or negative. You also should get a percentage, rating or other number that describes how strongly (or weakly) the cells respond to the hormones.
What the results mean: Positive means the hormones likely are fueling the growth of the cancer cells.
You can take hormonal therapies that block the effects of estrogen or lower its levels in the body, with the goal of slowing or stopping the cancer’s growth.
A note on results: Not all labs use the same testing method, nor do they report the results in exactly the same way. Ask your treatment team to explain your results.
What it is: Tells whether the cancer cells make too much of a protein called HER2 (human epidermal growth factor receptor-2), which receives signals telling the cells to grow and divide.
How it is determined: Usually with a test called IHC (immunohistochemistry), which measures the amount of HER2 protein on the cell surface, but sometimes with tests that look for extra copies of the HER2 gene. The HER2 gene controls the production of the HER2 protein and how the cells grow, divide and repair themselves.
Possible results: Positive or negative.
What the results mean: Positive means the cancer can be treated with trastuzumab (Herceptin), which blocks the HER2 receptors from picking up as many growth signals, or other targeted therapies, if you have Stage IV breast cancer.
A note on results: The IHC test gives the tissue a score: 0 to 1+ gets reported as HER2 negative, 3+ gets reported HER2 positive, and 2+ gets reported as “indeterminate.” If you get a score of 2+ or sometimes 1+ on the IHC test, you can ask that another type of test called “FISH” be done.
Read more about the providers who helped us to write this page in our Guide to Understanding Treatment Decisions.