A benign result on a biopsy report means the tissue sample did not contain cancer cells. A malignant result means cancer cells were found. The report will include additional information about the cancer.

A breast biopsy involves taking a small sample of breast tissue so it can be examined under a microscope.

Your doctor might order a breast biopsy after finding something suspicious on a mammogram or a breast ultrasound. A biopsy is the only way to determine whether a breast lump is noncancerous (benign) or cancerous (malignant).

After thorough analysis, a pathologist (a doctor who specializes in examining tissue samples) prepares a detailed report. It contains a lot of information and terms you may not be familiar with.

In this article, we’ll discuss some of the main items included in breast biopsy results and talk about what happens next.

Here are some items that might appear on your pathology report after a needle biopsy:

  • Specimen/gross description: details such as the size, weight, and color of the tissue being analyzed
  • Microscopic description: how the cells look under a microscope
  • Special tests or markers: to check for proteins and cell growth rate
  • Biomarkers: estrogen receptor (ER) status or progesterone receptor (PR) and HER2 status
  • Diagnosis or summary: a report of the findings

The main result from a breast biopsy indicates whether the tissue sample contained cancer cells. Some research suggests that about 75% of breast biopsies performed in the United States come back with a benign (noncancerous) result.

Keep in mind that different labs may use different terminology, and your report may go into greater detail.

A benign result means the tissue sample didn’t contain cancer cells. Benign conditions and changes that can occur in your breasts include:

If you see the words “high risk” on your report, it means you may have a condition that’s associated with higher risk of developing breast cancer in the future, such as:

A malignant result means cancer cells were found in the sample. Your report will provide additional information about the cancer.

Invasive or noninvasive

If the report includes the words “ductal carcinoma in situ (DCIS),” it means you have noninvasive cancer. This type of cancer stays within the milk duct where it started. DCIS is considered stage 0 breast cancer or precancer.

Invasive cancers can invade nearby tissue and spread beyond the breast. They’re sometimes called infiltrating cancers. These include invasive ductal carcinoma, which begins in the milk duct, and invasive lobular carcinoma, which begins in the lobules.

Hormone receptors

Breast cancers are checked for estrogen receptors (ER) and progesterone receptors (PR). They’re reported separately as positive, weakly positive, or negative. Most labs report ER/PR on a percentage of 0% to 100%. Some labs use a score from 0 to 8.

If your cancer tests positive for these hormone receptors (HR), the cancer is using hormones to fuel growth. This is important because it means you can benefit from hormone therapy.

HER2

Breast cancer is checked for overexpression of a protein called human epidermal growth factor receptor 2 (HER2). Due to recent changes in the landscape for breast cancer, labs also test for HER2-low expression.

Using immunohistochemistry testing, the results are reported as:

  • 0 or 1+: HER2-negative
  • 3+: HER2-positive
  • 2+: unclear or equivocal

An unclear result means further testing is needed. Overexpression of HER2 can make breast cancer grow and spread faster. But a positive result means your treatment can include drugs that target HER2.

Grade

The grade of cancer describes how different the cells look from normal cells and how fast they’re reproducing:

  • Grade 1 means the cancer cells are well differentiated. They look a little different from normal cells and are usually slow-growing.
  • Grade 2 covers moderately differentiated cancer cells. They don’t look normal and are growing at a faster rate than normal cells.
  • Grade 3 means the cancer cells are poorly differentiated. They look a lot different from normal cells and are growing much faster.

How long does it take to receive results?

Getting a biopsy can be a stressful event, and you won’t get your breast biopsy results right away. The samples must be sent to a lab where a pathologist can analyze them. The report will then go to the doctor who ordered it.

Most of the time, this takes about a week, but it can take longer (up to 2 weeks) depending on where the biopsy is done.

It’s perfectly normal to worry while you wait, but a longer wait doesn’t say anything about the results. If you don’t get a call within the expected time frame, follow up with your doctor.

Your next steps will be determined by the results of your pathology report.

Benign results

If your pathology report states that the cells were benign, that means no breast cancer was found. Your doctor will give you the particulars of the diagnosis. If the biopsy results aren’t clear to you, consider asking:

  • Do I need any kind of treatment right now?
  • Is this something that I should follow up on? If so, when and how?
  • Am I at higher risk of breast cancer in the future?
  • When do my risks change, and how often should I be screened?

Malignant results

If the pathology report indicates breast cancer, your next step will likely be to visit with a breast cancer specialist, such as a breast surgeon or an oncologist.

Your detailed pathology report will help with clinical staging of the cancer. The stage, along with breast cancer type, will help guide the next steps. These may include additional tests or scans to see whether the cancer has spread to other areas, such as nearby tissues or more distant organs.

Your doctor might also recommend genetic testing at this time. This can determine whether you carry gene mutations associated with other types of cancer as well.

If surgery is indicated to remove the tumor, the surgeon will take more samples for biopsy. This will generate a new pathology report with additional information such as:

Your oncologist can use this information to decide whether your treatment plan needs adjusting.

The wait for breast biopsy results can be a stressful time. And when you get them, the medical terminology can be confusing.

The biggest piece of information is whether the sample contains cancer cells. If no cancer cells are found, the report will describe what was found and your doctor can advise you on whether you need treatment or follow-up testing.

If the sample does contain cancer cells, the report will specify whether it’s invasive or noninvasive. The report will also include other details, such as HR and HER2 status, that can help determine your best treatment options.

Additional biopsies will happen during surgery to remove the tumor. That pathology report will add to what’s already known and help guide the rest of your breast cancer treatment.

When in doubt about your breast biopsy results, it’s best to speak with your oncologist.