When the researcher becomes the patient: Grasping the full impact of cancer

For 15 years, Mass General Brigham Cancer Institute researcher Jennifer Guerriero, PhD, has dedicated her career to advancing breast cancer research and improving treatment options for patients. Her work spans multiple breast cancer subtypes, including studies using hormone receptor-positive tumor samples collected from patients at Mass General Brigham.

This past spring, that life's work became even more personal.

Guerriero, 43, was diagnosed with an early-stage form of hormone receptor-positive breast cancer - a disease she had spent years investigating in her own laboratory. The diagnosis came after a routine screening mammogram and caught the disease at an early stage, before a detectable lump had formed.

Now a patient and an advocate for early detection, Guerriero finds herself face-to-face with the disease she has dedicated decades of her career to understanding.

"I knew the science, I knew the biology, but I never expected to hear the words that I had breast cancer," Guerriero said.

It was also a humbling reminder that understanding cancer through the research lens is very different from experiencing it as a patient.

"If I had waited to feel that lump, I would have had very different options and a very different prognosis," she said. "This really emphasizes the need for early detection using mammograms."

As she navigated her own diagnosis, Guerriero suddenly found herself facing many of the same decisions and uncertainties she had spent years studying as a researcher.

A family connection comes full circle

Long before dedicating her career to studying the biology of breast cancer - and becoming a patient herself - the disease touched Guerriero's own family. One of her earliest memories is of her grandmother undergoing a double mastectomy and treatment.

Even as a child, she found herself wondering why some patients were cured while others were not.

That same curiosity became the motivation behind her research, inspiring her to become a cancer researcher and dedicate her career to uncovering the biological factors that drive breast cancer and influence treatment outcomes.

Specifically, she has been investigating the role of immune cells in breast cancer and devising ways to alter the behavior of immune cells that help tumors resist treatment.

The benefits of early detection

After being diagnosed with early-stage, high-grade, hormone-receptor-positive breast cancer, Guerriero met with Barbara Smith, MD, PhD, a renowned breast cancer surgeon at the Mass General Brigham Cancer Institute and, coincidentally, her boss in the Mass General Brigham Department of Surgery.

Smith shared encouraging news. The cancer had likely been years away from becoming detectable as a lump. Because it was caught so early, Guerriero had more treatment options available to her and an excellent prognosis.

Smith talked Guerriero through those treatment options and helped her weigh the decision between a lumpectomy and a double mastectomy.

"My best shot of not having recurrence was a double mastectomy," Guerriero said.

Smith performed that surgery on Guerrero at Brigham and Women's Faulkner Hospital this summer. After recovering from the procedure, she returned to the lab and is now cancer-free. Her journey has made her an advocate for early detection as a researcher and a patient.

Throughout treatment and recovery, she drew strength from family, friends, her community and her care team at Mass General Brigham Cancer Institute.

"When you're sick, there's not much that can give you reassurance or make you feel better," she said. "Knowing that your clinical care team is the best in the world feels very good and is reassuring as you go through a cancer diagnosis, surgery and recovery."

Since turning 40, Guerriero had marked each annual mammogram with a selfie on social media. She shared the posts as a reminder to the women in her network about the importance of screening and to encourage them to schedule their own appointments.

This year, however, the response was different.

After sharing that her routine mammogram had detected breast cancer, Guerriero received calls and text messages from friends, colleagues, and acquaintances who told her they had scheduled their own screenings because of her story. What began as a personal health update became a powerful reminder of how sharing one experience can influence others to take action.

"This is one of the bravest, most generous things I've ever read," said one Facebook user in response to her post. "Turning your own diagnosis into a call for others to protect themselves shows exactly who you are: strong, compassionate and endlessly committed to saving lives."

"We're so sorry you have to go through this," wrote another user. "I'm going to schedule my mammogram right away!"

"Those pictures and texts of women going to get routine screening mammograms really pushed me through some of my hardest days," Guerriero said. "I hope that the story can inspire others to get their mammogram."

A new perspective on research

Guerriero's experience as a patient also changed the way she thinks about the tissue samples her laboratory studies. Her lab analyzes breast tumors donated by patients to identify strategies that may stop cancer growth or activate the immune system against it. Some of those approaches are already being evaluated in clinical trials.

After undergoing biopsies and surgery herself, Guerriero saw firsthand what it means to donate tissue for research.

"Every tissue represents a patient," she said. "I now understand - not only as a scientist, how invaluable that tissue is - but as a patient, how meaningful it is to go through breast cancer surgery or a biopsy and to provide your own specimens for research purposes."

A deeper purpose

For years, Guerriero has dedicated her career to understand how the immune system interacts with breast tumors - and developing innovative approaches to harness its power to treat breast cancer.

Her experience as a patient has strengthened her commitment to both early detection and the research that could lead to the next treatment breakthrough.

"Get screened," she said. "Support the science that will lead to the next discoveries and therapeutic treatments for breast cancer patients."