Women's Health

Understanding a Breast Cancer Biopsy Report

Understanding a Breast Cancer Biopsy Report

When a physician suspects that a patient may have breast cancer, they will likely call for a biopsy to be done in order to make an exact diagnosis and begin the prognosis stage. In order to do a biopsy tissue, cells, or lumps must be removed from the breast and sent to the lab in order to be tested. A pathologist usually conducts the test and will examine the cells under a laboratory microscope to check for certain characteristics.

After the pathologists have completed the testing phase, they will usually create a report that explains their findings and their suggested diagnosis. The report may be referred to as a pathology report or a biopsy report and might include supporting results from any other tests or screenings that the patient has had including ultrasounds, mammograms, or MRIs. Physicians use the information that is displayed in biopsy reports to make an affirmative diagnosis and to begin formulating the best course of action for treating the ailment or disease.

According to the National Breast Cancer Foundation, most biopsy reports can take between one and two weeks to finish. Before a physician completes a biopsy, patients are advised that they should ask their physician how the results of that biopsy will be communicated. Waiting for the results of a biopsy can often be the most difficult part of having one done, but having a generalized timeline of when the patient will find out what's going on can help to make the time easier to wait out and relieve the stress and fear that many feel while waiting.

Breastcancer.org has published a 45-page long guide that outlines what's included in most biopsy reports and most physicians will make the final say as to whether or not the news will need to be delivered and explained in person or over the telephone. Most physicians will explain their preference with the patient before starting the biopsy.

While the exact pieces of information that the biopsy report includes may vary depending on circumstances and the physician's preference, most will include similar items.

Cell Type

The final determination as to whether or not the cells from the samples are cancerous or not and whether or not they are deemed benign (non-cancerous) or malignant (cancerous). The Johns Hopkins Breast Center estimates that 80 percent of all biopsies taken end up being benign. However, if the biopsy states that the cell type is malignant, that means the pathologist detected cancer and further information will follow.

Type of Cancer

If the cells are found to be malignant and cancer is present, then the next piece of information is usually whether the cancer is invasive (infiltrating) or non-invasive (in situ). In invasive breast cancer, the cancerous cells have moved beyond the normal breast tissue and moved into other tissues or parts of the body through the lymph nodes or the blood stream. With non-invasive breast cancer, the cancerous cells have remained in the lobules or milk ducts and have not spread to any other tissues or parts of the body.


In addition to cancer status and type, the pathologist will also include in the biopsy report any information regarding the grade of the tumor cells. According to the National Cancer Institute, a tumor-grading scale is a method for measuring how cells should look under a microscope. Most tumor-grading scales provide detailed explanations of how healthy tumor tissue and tumor cells should look under a microscope, and how unhealthy tissue and cells actually look. If the cells are described as well-differentiated, it means that the cells look like healthy breast cells. If the cells are labeled as undifferentiated or poorly differentiated, it means that the cells look abnormal and could mean that they lack normal tissue structures.


Determining the stage of a cancer is not the same as analyzing the grade of a cancer. According to the National Cancer Institute, determining the stage of a cancer is the process of explaining the size of a tumor, the extent of the original tumor, and whether the cancerous cells have spread to other parts of the body. The stage of a cancer will also play a big role in helping a physician decide whether or not more testing is required and what the best course of action might be. On the other hand, grading a cancer determines whether or not tumors are likely to grow by analyzing the cells of the tumors. A grade of X means that the grade could not be determined, a grade of 1 means that the tumor is rated as least aggressive, and a rating of 4 means that the tumor is rated as fastest growing.

Most breast cancer specialists will use the Elston-Ellis modification of the Scarff-Bloom-Richardson grading system (also called the Nottingham grading system) to determine how the tumors rates as far as mitotic rate, nuclear grade, and tubule formation, according to the National Cancer Institute. Mitotic rate determines how fast the cancerous cells are growing and dividing, nuclear grade refers to the shape and size of the nucleus of the cells, and tubule formation refers to how many normal milk duct structures are inside the tumor tissue. These three characteristics result in rating numbers which are then added up to give a total score. A total score of 3 to 5 is a G1 rating, a total score of 6 to 7 is a G2 rating, and a total score of 8 to 9 is a G3 rating. G1 means a low grade, G2 means an intermediate grade, and G3 means a high grade. The lower the grade, the better the prognosis usually is.

Hormone Receptor Status

Hormone receptor status refers to how tumor cells are fed. Most breast cancers are driven by hormones, which means that the body makes the hormones that make the tumor cells grow. Hormone receptors are actually proteins that are on or in cancer cells and receive the hormones necessary for the cells to grow.

There are five primary types of hormone receptor designations that may be given on the biopsy report.

  • ER+ means that the cancer is estrogen-receptor positive. Approximately 80 percent of breast cancers are ER+.
  • ER+/PR+ means that both progesterone and estrogen receptors were found in the sample. Approximately 65 percent of breast cancers are ER+/PR+.
  • ER+/PR- means that the cancer is only being fed by estrogen. Approximately 13 percent of breast cancers are ER+/PR-.
  • ER-/PR+ means that the cancer is being fed by progesterone. Approximately 2 percent of breast cancers are ER-/PR+.
  • ER-/PR- means that the breast cancer has no hormone receptors. Approximately 25 percent of breast cancers are ER-PR-.

A patient's hormone receptor status is usually a pretty important tool for helping the doctor determine the next best course of action or treatment. If the cancer is found to be fed by hormones, the treatment plan will most likely include hormone therapies like aromatase inhibitors or tamoxifen. According to the Susan G. Komen organization, hormone therapy may be able to stop the growth of tumors by preventing cancer cells from receiving the hormones they need in order to grow.


About Breast Cancer: Lab Tests. (n.d.). [Web]. In National Breast Cancer Foundation, Inc. Retrieved on 09/11/2017 from: http://www.nationalbreastcancer.org/breast-cancer-lab-tests

Contents of a Pathology Report. (n.d.). [Web]. In Susan G. Komen. Retrieved on 09/11/2017 from: http://ww5.komen.org/BreastCancer/ContentsofaPathologyReport.html

Getting Your Pathology Report (n.d.). [Web]. In BreastCancer.org. Retrieved on 09/11/2017 from: http://www.breastcancer.org/symptoms/diagnosis/getting_path_report

Howley, E. (2017, August 8). How Do I Read My Breast Cancer Biopsy Report? [Web]. In US News. Retrieved from: http://health.usnews.com/health-care/patient-advice/articles/2017-08-08/how-do-i-read-my-breast-cancer-biopsy-report

Tumor Grade (n.d.). [Web]. The National Cancer Institute. Retrieved on 09/11/2017 from: https://www.cancer.gov/about-cancer/diagnosis-staging/prognosis/tumor-grade-fact-sheet