A new study has found that a person’s gut bacteria could determine their risk of skin cancer returning after treatment. Researchers from NYU Langone Health and its Perlmutter Cancer Center analysed stool samples from 674 melanoma patients enrolled in a global clinical trial, and found that differences in key bacterial groups predicted cancer recurrence with up to 94% accuracy.
Melanoma, a type of skin cancer often linked to sun exposure, recurs in 25 to 40% of patients after surgery and immunotherapy. The study, published in the journal Cell, examined how trillions of bacteria living in the digestive tract interact with immune cells, influencing patients’ responses to immunotherapy.
However, researchers discovered a catch: the bacterial markers that most accurately signal recurrence risk differed depending on where the patient lived. Participants came from North America, Eastern Europe, Western Europe, Australia, and other regions. By grouping patients based on gut microbiome similarity, the team found that a bacterial signature from North American patients could predict recurrence in others only if they had a similar microbial fingerprint.
“Our study identified for the first time gut bacterial types that can serve as markers of increased recurrence risk in these specific patients, which will help tailor treatment,” said senior author Dr Jiyoung Ahn, a professor at NYU Grossman School of Medicine.
Co-author Dr Richard B. Hayes added: “In the future, we envision analysing a patient’s microbiome before treatment, comparing it to a global database, and providing a reliable prognosis that guides therapy from the start.”
