Hearing that something suspicious was detected on your mammogram or breast ultrasound can be concerning. Most likely, you were told the next step is to follow up with a biopsy. But what exactly is a biopsy, and what will the doctor discover from the biopsy results?
A breast biopsy involves taking a small sample of breast tissue to examine it under a microscope by a pathologist. Up to this point, you’ve probably had a few different tests, such as a mammogram and possibly an MRI or ultrasound, that suggest the presence of cancer. A biopsy is the only definitive way to confirm whether a breast lump is noncancerous (benign) or cancerous (malignant).
The type of biopsy you have depends on several factors, such as the size and location of the lump, the number of abnormalities present, your overall health, and your personal preferences. The most common types of biopsy used for breast cancer diagnosis are:
After completing a breast biopsy, the samples are sent to a pathologist. This doctor will review the cells under a microscope and then create a comprehensive report detailing the important characteristics of the sample. This includes the size, weight, and color of the tissue, as well as anything they notice about the cells under a microscope, protein tests, cell growth rate, and a diagnosis or summary of the findings. It will also likely indicate whether the sample is hormone receptor-positive.
The good news is that most breast biopsies produce benign results. However, even if your report comes back cancer-free, you will still see certain terms describing these non-cancerous changes in your breast, such as:
Unless you experience symptoms, you likely won't need treatment. Most benign breast conditions also do not increase your risk of future breast cancer. Discuss any concerns about your benign breast biopsy results with your doctor.
If your breast biopsy results confirm the presence of cancer cells, your pathology report will provide details about the specific characteristics of the tumor. This information is crucial for your cancer care team to develop a treatment plan. Here is some of the information you may see in your pathology report and what it means:
The type of breast cancer typically refers to where it started and whether it’s invasive or noninvasive.
Noninvasive (in situ) breast cancer is contained in the milk duct where it started. The report will list this as ductal carcinoma in situ (DCIS), which is considered a precancer or stage 0 breast cancer.
Invasive (infiltrating) breast cancer has invaded nearby tissue and spread beyond where it initially started in either a milk duct, called invasive ductal carcinoma, or in the lobe of the breast, called invasive lobular carcinoma (ILC).
In addition to the information above, your biopsy may have found cancer cells for one of these types of breast cancer:
Read our related blog: What is Inflammatory Breast Cancer?
The cancer grade measures how different the cancer cells look compared to normal cells and how fast they are growing:
Higher-grade breast cancers will likely require more treatments to treat them successfully compared to lower-grade cancers.
The cells in your breast tissue sample will be examined for hormone receptors. Proteins on the cancer cells can attach to estrogen or progesterone hormones, causing the cancer cells to grow faster. If the cancer tests positive for these hormone receptors, it means the cancer is using hormones to grow, and hormone therapy may be a suitable treatment option.
Your pathology report may list hormone receptor status information in the following ways:
Learn how hormone receptor status affects breast cancer treatment.
HER2 is a protein that controls breast cell growth. If the biopsy report is “positive” for HER2, the cancer is using this protein to grow. If your pathology report shows a HER2 designation of "equivocal," it means your cancer's HER2 status is uncertain. A second test may be recommended to determine your cancer's HER2 status. If your cancer expresses HER2 on one test but not the other, it may be classified as HER2-low.
The biopsy report, along with imaging and lymph node involvement reports, will determine the stage of cancer ranging from 0 to IV (4). The treatments recommended are specific to the type of breast cancer, the stage, and the grade. Your breast cancer oncologist and surgeon will meet and discuss the best next steps for you. Feel free to ask questions and discuss what’s next for you.
If you or a loved one had biopsy results that confirmed a breast cancer diagnosis, the team at Compass Oncology is here to support you every step of the way. It’s time to choose your medical oncologist to lead your treatment team.
Schedule a consultation with a breast cancer specialist at one of our cancer centers in the Portland, Oregon, or Vancouver, Washington areas to learn more about a personalized treatment plan. We can also provide a second opinion to help you make the best decisions for you.