Researchers have pinpointed a potential cause for the increasing incidence of colorectal cancer among patients under 50: a fungus commonly associated with nail and skin infections.
According to Axios, doctors at Georgetown University developed this innovative theory while studying changes in the gut microbiomes of cancer patients.
“A lot of people blame obesity and diabetes,” noted Benjamin Weinberg, a gastrointestinal medical oncologist at Georgetown. “But we have these patients who run marathons and they eat [healthy diets] and they’ve got very advanced colorectal cancer.”
The researchers from the Washington, D.C. university analyzed microbial DNA samples extracted from colorectal cancer tumors in patients diagnosed either under 45 or over 65 years old.
They discovered that tumors from younger patients more frequently contained the fungus Cladosporium sp., which typically inhabits the skin and nails and is rarely found in the gut.
While the mechanism by which this pathogen might contribute to cancer remains unclear, one hypothesis is that it could damage cell DNA.
“We think there was some sort of exposure [to the bacteria] 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 elaborated.
Colorectal cancer, encompassing cancers of the colon and rectum, ranks as the third most prevalent cancer in the United States and is the second leading cause of cancer-related deaths, according to the National Institutes of Health.
The five-year survival rate for patients with this illness stands at 65%.
The National Cancer Institute has reported 153,020 new cases of colorectal cancer this year, with 19,550 of these cases occurring in individuals under 50 years old. It is a major cause of cancer-related mortality in this age group in the US, with incidence rates on the rise.
This trend is concerning, particularly as the incidence of colorectal cancer has markedly decreased among older adults, largely due to routine colonoscopies and reduced smoking rates.
The researchers plan to present their findings at the upcoming American Society of Clinical Oncology conference next week.
