A Vaccine for Breast Cancer?

A shot to treat and prevent breast cancer may be closer to reality than you think.

by Lara DeSanto Health Writer

What if treating—or preventing—breast cancer was as easy as getting a shot? It could be a reality sooner than you think.

Researchers at the Mayo Clinic in Jacksonville, Florida, have developed a vaccine that may stop breast and ovarian cancers from recurring—and may even prevent them from occurring in the first place, they say.

“It is reasonable to say that we could have a vaccine within eight years that may be available to patients through their pharmacy or their doctor,” Mayo Clinic investigator Keith L. Knutson, Ph.D., said in an interview with Forbes. The vaccine triggers the immune system to latch onto and kill cancer cells in the body.

While the research is still in the early stages, a Florida woman, Lee Mercker, is now cancer-free after being the first to receive the vaccine in a clinical trial. Mercker was diagnosed with an early form of breast cancer called ductal carcinoma in situ (DCIS) stage 0 in March 2019 and jumped at the chance to participate in the vaccine trial.

Mercker received a shot of the vaccine in a series over 12 weeks. The vaccine mobilized her immune system against the cancer cells and her tumor shrunk. Because the vaccine is still in the trail phases, she also had a double mastectomy (surgical removal of both breasts) to ensure she was cancer-free. The Mayo Clinic researchers will examine the removed tissue to glean insight into how the vaccine works.

“I feel like I walked on the moon,” she said in an interview. “I worked in an industry with tons of women and I saw all kinds of stories, and it’d just be really nice to stamp this [breast cancer] out.”

Two other patients are receiving the vaccine as part of the trial, says Dr. Knutson, and they are searching for more participants. And this is just one of several vaccines the Mayo Clinic is working on to help prevent and treat breast cancer.

“We know that [the vaccines] are safe. We know that they stimulate the immune system [to fight cancer],” Knutson told Forbes. “We know that they have had a positive impact on ovarian and breast cancer. We haven’t seen any adverse events that are causing problems other than irritation in the area like a flu vaccination. Now we must convince the FDA [U.S. Food and Drug Administration], through solid, rigorous clinical trials that we’re seeing what we’re seeing.” And while that process could take several years, researchers are extremely hopeful.

Risk Factors and Warning Signs of Breast Cancer

The type of cancer Mercker had that this vaccine targets, DCIS, occurs when abnormal cells grow in the milk ducts of the breast, per the Mayo Clinic. Most people with this cancer get diagnosed after a mammogram to routinely screen for cancer or to evaluate a lump they may have found.

And that’s the story for people with other types of breast cancers, as well. And until we have a vaccine to prevent breast cancer altogether (fingers crossed), it’s important to know your breast cancer risk factors and watch for warning signs.

Risk factors for breast cancer, per the Centers for Disease Control and Prevention (CDC), include:

  • Age. Most people diagnosed with breast cancer are over 50.

  • Genetic mutations. Certain genetic mutations, like BRCA1 and BRCA2, significantly increase your risk of breast and ovarian cancer.

  • Past breast cancer or non-cancerous breast disease. If you’ve had breast cancer in the past, you’re more likely to get it again. Certain breast diseases like atypical hyperplasia also up your risk.

  • Family history of breast cancer. If you have a mother, sister, or daughter with a history of this cancer, you’re more likely to develop it yourself.

  • Reproductive history. If you started your period before age 12 or started menopause after age 55, you’re more likely to get breast cancer.

  • Past use of diethylsilbestrol (DES). This drug was given to some pregnant women in the U.S. between 1940 and 1971. If this was you—or your mother—you have an increased risk of breast cancer.

  • History of radiation therapy. If you’ve had radiation therapy in your chest before age 30, you’re at a higher risk of getting breast cancer.

  • Dense breasts. The type of tissue in dense breasts can make screening with mammogram trickier, so people with dense breasts may be at increased risk of breast cancer.

Here are some signs to watch for the could potentially indicate breast cancer, according to the CDC:

  • A new lump that develops in your breast or armpit

  • Dimpling or irritation of the skin on your breast

  • Thickening or swelling in the breast

  • Flaky or red skin in the nipple area or other areas of the breast

  • Pain in the nipple area or a pulling in of the nipple

  • Nipple discharge (not breast milk), such as blood

If you have any of these signs, make an appointment with your doctor—while these signs can often be benign (meaning not cancerous), it’s important to get checked out to be sure.

Lara DeSanto
Meet Our Writer
Lara DeSanto

Lara is a former digital editor for HealthCentral, covering Sexual Health, Digestive Health, Head and Neck Cancer, and Gynecologic Cancers. She continues to contribute to HealthCentral while she works towards her masters in marriage and family therapy and art therapy. In a past life, she worked as the patient education editor at the American College of OB-GYNs and as a news writer/editor at WTOP.com.