Information About Your Tumor
After you have a biopsy, the pathologist sends a report describing the features of your tumor to your doctor. This includes the results of special tests performed on the tumor tissue that are important in determining which treatment will be best for you.
The two most informative factors in determining your treatment are the tumor size and the extent of lymph node involvement. Other helpful information is tumor grade, hormone receptor status, ploidy and S-phase.
- Tumor size - is noted in centimeters.
- Lymph node involvement - a tumor that grows into the blood vessels or lymph nodes is considered more likely to spread. The pathologist will count the number of lymph nodes that have breast cancer cells in them.
- Tumor grade - The grade of the tumor is determined by how abnormal the cancer cells appear when examined under a microscope. Cells that are more normal appearing, Grade I, tend to be less aggressive. Cells that are the least normal appearing, Grade III, are more aggressive.
- Estrogen receptor (ER) and Progesterone receptor (PR) - are proteins found in some breast cancer cells to which estrogen and progesterone will attach. A special test measures the amount of these proteins in breast cancer tissue. Breast cancer cells that are estrogen receptor positive (ER+) are more likely to need the estrogen to grow. Breast cancer cells that are progesterone positive (PR+) also are more likely to need estrogen to grow. Breast cancer that is ER or PR positive usually responds to hormonal estrogen treatment, like tamoxifen.
- Ploidy and S-phase (proliferative fraction) - A special technique used to tell whether abnormal amounts of DNA are present in the cancer cells (aneuploidy) and how many cells are dividing at any point in time ( percent S-phase). These characteristics can sometimes be used to estimate the aggressiveness of the tumor.
- HER2/neu - is the gene that makes Human Epidermal growth factor Receptor 2. The protein produced is HER2/neu. In normal breast tissue cells, the HER2 gene produces a protein that is found on the cell surface. This protein is thought to play a role in normal cell growth by signaling the cell to divide and multiply. Cancerous breast tissue cells that have abnormally high amounts of HER2 can sometimes divide at a faster rate. About 20 percent of women with breast cancer have abnormally high HER2 amounts. This marker can be helpful in determining whether Herceptin is a treatment option for a woman with breast cancer.
- Tumor markers - Tumor cells sometimes produce "markers". Tumor markers are substances sometimes found in increased amounts in blood or in the presence of breast cancer. Tumor markers that are sometimes used in the management of breast cancer include the CEA and CA 27-29.
In some situations, they can be useful, in addition to other means, for assessing response to treatment. They have not been shown to be useful in detecting if a cancer has come back or in detection of early breast cancer.