Bacteria Types Differ in Early- vs. Late-Onset Colon Cancer Tumors



A recent study found the gut microbiome of colon tumors vary, depending on whether the patient was diagnosed with early-onset or late-onset disease.

Study finds difference in colon tumor microbiomes

According to new research from Georgetown University’s Lombardi Comprehensive Cancer Center, the microbiome of patients with colon cancer can differ greatly.

The research team found that the type and amount of viruses, fungi and bacteria in the colon tumors of patients varied significantly, depending on whether the patients were diagnosed with early-onset colon cancer compared to late-onset colon cancer.

Early-onset colon cancer incidence is rising.

Colon cancer rates have been decreasing in adults older than 55, partly due to increased screening for the disease. However, colon cancer incidence continues to rise in young adults. In the last 10 years, the number of adults younger than 55 with colon cancer has doubled, and the incidence rate has increased from 11 percent in 1995 to 20 percent in 2020.

Microbes and the intestinal lining

Scientists have known that microbes can cause inflammation in tissues, which can mutate DNA cells in the colon lining. They also are aware that a certain type of bacteria called Fusobacterium nucleatum (F. nuc) can suppress immune response in the colon and make it more prone to cancer.

The study examined 917 types of fungi and bacteria in colon tumors. F. nuc was one of the most common types of bacteria, and it appeared in about 30 percent of both early- and late-onset colon tumors. The researchers were also able to categorize specific bacteria and fungi that were more common in early-onset tumors and late-onset tumors.

“Younger people with colorectal cancer have more biologically aggressive cancers, and whatever survival benefit they have by being younger is outweighed by the more aggressive tumor biology. We also know that for the most part, genetics doesn’t explain the recent rise in young-onset disease,” said Benjamin Adam Weinberg, MD. “But we have trillions of bacteria residing in our body, including in our gut, some of which are implicated in the development of colorectal cancer; hence, we think the microbiome may be an important factor in the development of the disease, as it is involved in the interplay between a person’s genetics, environment, diet and immune system."

Dr. Weinberg is an associate professor of medicine at Georgetown Lombardi. He hopes the new study may provide insight on why young-onset colon cancer rates continue to increase. With the current findings and plans to continue the research, the team wants to continue to explore how microbiome and other factors influence colon cancer development.

Early detection and treatment of colon cancer

Because young-onset colon cancer is usually more aggressive, it is essential to be familiar with symptoms of the disease. Some symptoms of colon cancer include the following:

  • Abdominal pain
  • Rectal bleeding
  • Weakness or fatigue
  • Constipation or diarrhea
  • Thin, pencil-like stools
  • Weight loss

Call a gastroenterologist for a colonoscopy.

If you are experiencing symptoms, you should see your physician. Your doctor may suggest that you schedule a colonoscopy. Although there are several types of colon cancer screening procedures, a colonoscopy is the most effective screening available because it can detect and prevent colon cancer.

Do you need help finding a gastroenterologist near you? Our GI centers are located nationwide. Call today to make an appointment.