Colorectal cancer spike in young people could be caused by fungus

Researchers have found a possible reason for a spike in the rate of colorectal cancer cases among patients under 50: a fungus that usually blamed for nail and skin infections.

Doctors at Georgetown University came up with the novel theory while tracking changes in the gut microbiomes of cancer patients, Axios reported.

“A lot of people blame obesity and diabetes,” Benjamin Weinberg, a gastrointestinal medical oncologist at Georgetown told the outlet. “But we have these patients who run marathons and they eat [healthy diets] and they’ve got very advanced colorectal cancer.”

The Washington, D.C. university looked at microbial DNA samples from the tumors of colorectal cancer patients who were either under 45 or over 65 when diagnosed.

They found that tumors from younger patients were more likely to contain the fungus Cladosporium sp., which is typically rarely found in the gut, and causes skin and nail infections. It’s still not clear how the pathogen could lead to the cancer, but one theory is it could be responsible for damaging cell DNA.

“There was some sort of exposure [to the bacteria] we think in the 1970s or 1980s — maybe everybody started taking antibiotics for ear infections or they stopped breastfeeding — something happened where this cohort is seeing this rise and we don’t know why,” Weinberg continued.

Colorectal cancer, which includes cancers of the colon and rectum, is the third most common form of cancer diagnosed and the second leading cause of cancer death in the country, according to the National Institutes of Health.

The five-year survival rate for patients with the illness is 65%.

The National Cancer Institute reported 153,020 new colorectal cancer cases this year, with 19,550 of them in people under 50 years old. It is a leading cause of cancer death among people under 50 in the US, with new diagnoses rates climbing.

The surge is also alarming considering that the rate of colorectal cancer has gone down drastically among older adults, mainly due to regular colonoscopies and lower smoking rates.

The research will present their findings to the American Society of Clinical Oncology next week.