After you finish treatment for early-stage breast cancer, you might worry about the cancer coming back. This is called a recurrence. Even though treatment can lower the chances of recurrence, everyone who has had breast cancer has a risk of it returning.

Doctors use different tools and information to estimate this risk. Although knowing what factors increase the chances of recurrence can be helpful, it’s important to remember that these are just estimates. Each person’s situation is unique, and it’s impossible to predict exactly what will happen. In this article, we’ll go over the main risk factors that doctors consider when estimating the chance of breast cancer recurrence.

Many Factors Go Into Calculating Risk

Your oncologist (cancer specialist) will consider many factors when estimating your risk of breast cancer coming back. These factors depend on your medical history, cancer type, and treatments. Doctors use data from thousands of other people with breast cancer to guide them. Keep in mind that these are averages, and your case might not follow the same patterns.

In general, the larger the tumor, the higher the chance that it can come back.

Some online tools or apps can give you a general idea of your risk, but these have limitations. They don’t take into account every detail of your health. Even if you have several risk factors, it doesn’t mean your cancer will return. Only a trained oncologist can give you the most accurate picture of your risk.

1. Larger Tumor Size

The size and specific characteristics of your original tumor play a big role in estimating your risk of recurrence. In general, the larger the tumor, the higher the chance that it can come back. For example, a tumor that is more than 5 centimeters across has a higher chance of returning than a tumor that is smaller than 2 centimeters.

2. Greater Lymph Node Involvement

Lymph nodes are small, bean-sized glands, located throughout your body, that help fight infections. Breast cancer can spread to the lymph nodes that are located near the breast. During surgery, your doctor will check these lymph nodes for signs of cancer. Lymph node involvement is one of the strongest factors that can predict whether or not the cancer is likely to recur.

If cancer is found in your lymph nodes, this could increase the chances of recurrence. The more lymph nodes that were affected, the higher the risk. If no cancer is found in the lymph nodes, your risk of recurrence is usually lower.

3. Hormone Receptor Status

Breast cancer cells are often tested to see if they have receptors for certain hormones like estrogen or progesterone. Cancers that are hormone receptor-positive (ER+ for estrogen or PR+ for progesterone) tend to grow in response to these hormones.

Hormone receptor-negative cancers are considered more aggressive and might carry a higher risk of coming back in the short term.

If your breast cancer is hormone receptor-positive, it may be less likely to return than hormone receptor-negative (ER- or PR-) cancer within the first five years after diagnosis. This may be because treatment with hormone therapy, such as tamoxifen, can help lower the chances of recurrence. Hormone receptor-negative cancers are considered more aggressive and might carry a higher risk of coming back in the short term. However, after five years, people with hormone receptor-positive cancer may have a higher risk of recurrence.

4. Positive HER2 Status

Doctors also test breast cancer cells to see if they have too much of a protein called human epidermal growth factor receptor 2 (HER2). If the cancer has too much HER2, it’s called HER2-positive. These types of cancers tend to grow and spread faster than HER2-negative cancers.

In the past, HER2-positive cancers had a much higher risk of coming back. However, treatments like trastuzumab (Herceptin) have greatly improved the outlook for people with HER2-positive cancer. Even with these treatments, HER2 status is still important in estimating recurrence risk.

5. Higher Cancer Grade

Cancer grade refers to what cancer cells look like compared to normal cells under the microscope. This information gives doctors an idea of how fast the cancer is likely to grow and spread. Breast cancer is graded on a scale from 1 to 3. Grade 1 cells look more like normal cells and grow slowly, while grade 3 cells are highly abnormal and grow quickly. Cancer grade refers to cell appearance and growth speed, while cancer stage describes how much the cancer has spread.

There’s a link between the cancer stage at your first diagnosis, the cancer cell grade, and the risk of recurrence. A higher-grade cancer (grade 3) has a greater chance of coming back after treatment compared to a lower-grade cancer, (grade 1 or grade 2), especially when combined with a higher stage of disease.

6. Positive Margins After Surgery

When your doctor removed the tumor, they also took out a small amount of healthy tissue around it, known as the margins. These margins are checked for any remaining cancer cells. If the margins are clear, meaning there are no cancer cells found, your risk of recurrence is lower.

But if cancer cells were found in the margins (called positive margins), there’s a higher chance the cancer could come back in the same area. If this happens, your doctor might recommend more surgery or radiation to lower the risk of recurrence.

7. Younger Age at Diagnosis

Your age at the time of your breast cancer diagnosis can also affect the risk of the cancer coming back. According to Breast Cancer Trials, a clinical research organization focused on breast cancer studies, younger women — especially those under 35 — are more likely to develop aggressive breast cancer, which increases the risk of recurrence. Older women, especially those diagnosed after menopause, generally have a lower risk of recurrence.

Age is just one piece of the puzzle, though. Your doctor will look at your age, along with other risk factors, to get a full picture of your recurrence risk.

8. Cancer Type and Subtype

The type of breast cancer you have also plays a role in estimating the risk of it returning. Certain types of breast cancer are more aggressive and come with a higher risk of recurrence, while others tend to grow more slowly.

Triple-Negative Breast Cancer

Triple-negative breast cancer doesn’t have receptors for estrogen, progesterone, or HER2. It accounts for about 15 percent of all breast cancers. This subtype of breast cancer tends to grow and spread quickly and is more likely to recur than other types. Around 40 percent of people with triple-negative breast cancer experience a recurrence, often within the first three years after treatment.

Inflammatory Breast Cancer

Inflammatory breast cancer is a rare and aggressive form of breast cancer that grows quickly and often involves the lymph nodes. Studies from Breastcancer.org have shown that around 50 percent of people with inflammatory breast cancer experience a recurrence in the first five years after diagnosis, making it one of the highest-risk types.

The type of breast cancer you have can greatly affect what your treatment plan is and what steps you should take to lower your recurrence risk. If you have triple-negative or inflammatory breast cancer, your doctor may recommend more frequent follow-up appointments or additional treatments to help lower your chances of recurrence.

Talk to Your Doctor

If you’re concerned about your risk of breast cancer returning, talk to your doctor. They can review your medical history, look at the factors mentioned here, and explain how they apply to your specific situation. It’s important to remember that having one or more of these risk factors doesn’t mean your cancer will come back. Many people with several risk factors go on to live cancer-free after their initial treatment.

Find Your Team

MyBCTeam is the social network for people with breast cancer and their loved ones. On MyBCTeam, more than 73,000 members come together to ask questions, give advice, and share their stories with others who understand life with breast cancer.

What concerns do you have about the risk of your breast cancer returning, and have you found ways to manage them? Share your experience with recurrence or fear of recurrence in the comments below, or start a conversation by posting on your Activities page.