Boston researchers discover differences in colon cancer tumor cells in younger patients

BOSTON — As colorectal cancer rates continue to rise among younger adults, a team of Boston researchers has identified differences in tumor cells that could potentially lead to new treatments.

The findings offer hope to survivors like Kristen Vincent of Orleans, who was just 37 years old when she learned she had stage 3 colorectal cancer.

"I was actually staged on my youngest daughter's second birthday. So, I found out that I had stage three cancer on her second birthday, and that was my biggest fear was missing their lives," Vincent said.

Her treatment at Dana-Farber Cancer Institute included 28 days of radiation, surgery, eight rounds of chemotherapy and 11 months with an ileostomy bag.

Throughout her battle, Vincent said she tried to maintain a positive outlook.

"Every day I would tell myself, cancer is not going to kill me today," Vincent said.

Now, Vincent has had five years of clean scans. She also has a few years participating in the Pan-Mass Challenge, raising more than $25,000 for cancer research at Dana-Farber, the hospital she credits with her positive outcome.

According to the American Cancer Society, colorectal cancer rates among people under 50 have been increasing by nearly 3% annually in recent years. The disease is now the leading cause of cancer-related death in that age group.

Researchers at Mass General Brigham, Dana-Farber Cancer Institute and the Broad Institute published a study examining why younger patients are increasingly being diagnosed with the disease.

"We've seen, as you said, this trend has been increasing, the incidence of colorectal cancer in individuals under 50 for some time. But we really didn't know why. We didn't know if the disease was different in younger people versus older people. And that's what our study aimed to address," said Dr. Ana Anderson, one of the study's senior co-authors.

The research team analyzed 189 tumors and more than 850,000 individual cell nuclei, including samples from more than 50 patients under age 50.

Anderson said researchers discovered differences in both the cells and gene expression within tumors from younger patients compared with older patients.

"Specifically, we found that stromal cells, the cells that kind of make the connective tissue, are in higher proportion compared to the malignant cancer cells in the younger patient tumors," Anderson said.

According to Anderson, those stromal cells can produce factors that suppress the immune system, making it harder for the body to fight cancer. They can also form a barrier that prevents drugs from entering tumors.

Researchers also identified differences in genes that may contribute to more aggressive forms of the disease.

The findings do not yet explain why more young people are developing colorectal cancer, but Anderson said they provide new avenues for researchers to investigate and could eventually lead to treatments specifically designed for younger patients.

"Before we were just trying to look for differences, now we have some differences that we can kind of dig into further to hopefully understand biology, and that could lead to interventions down the road," Anderson said.

For Vincent, the new research and potential for more is encouraging.

"It's exciting to me because the last thing I want is another young person with a young family to have to go through what I went through," Vincent said.

She is also encouraging others, particularly younger adults, not to ignore potential warning signs.

"If you are finding blood in your stool, you need to call your doctor right away if it is a consistent thing, because the earlier you're able to get the diagnosis, the higher likelihood you will have to beat this," Vincent said. "So please don't be embarrassed. Colonoscopies are not that bad. It's just so critical to catch it early."