What is already known
Oral squamous cell carcinoma is a malignant tumor that may occur anywhere within the oral cavity, and only half of the people with this type of cancer survive for five years after the diagnosis. Changes in the oral microbiota have been associated with oral cancer, and microbial signatures have been utilized as biomarkers of the disease. However, it’s unclear whether the mouth microbiota may also predict the recurrence of oral cancer.
What this research adds
Researchers analyzed 54 mouth swabs from people with oral cancer, including some who got cancer again after it had been treated. Bacteria such as Campylobacter, Porphyromonas, Actinomyces, Corynebacterium and Dialister were enriched in people with oral cancer recurrence. A model that included five microbial signatures predicted the recurrence of oral cancer in an independent group of 46 patients with an accuracy of about 75%.
Conclusions
The findings suggest that the composition of the mouth microbiota can be used to predict the recurrence of oral cancer.
Oral cancer is an aggressive tumor that comes back in about 20% of patients after they have been treated, with most recurrences occurring within the first two years. Now, researchers have found that patients who got oral cancer again after treatment have a different mouth microbiota than controls.
The findings, published in ACS Infectious Diseases, suggest that the composition of the mouth microbiota can be used to predict the recurrence of oral cancer. “In this study, we provided new insight into tools for the clinical prediction of [oral squamous cell carcinoma] recurrence from a microbiome perspective.”
Oral cancer, also called oral squamous cell carcinoma, is a malignant tumor that may occur anywhere within the oral cavity, and only half of the people with this disease survive for five years after the diagnosis.
Changes in the oral microbiota have been associated with oral cancer, and microbial signatures have been utilized as biomarkers of the disease. However, it’s unclear whether the mouth microbiota may also predict the recurrence of oral cancer.
To identify microbial biomarkers associated with oral cancer recurrence, researchers led by Wei-Ni Lyu at National Taiwan University in Taipei analyzed 54 mouth swabs from people with oral cancer, including some who got cancer again after it had been treated.
Microbial signatures
In the mouth microbiotas of patients with and without recurrent oral cancer, the dominant bacteria were Firmicutes, Proteobacteria and Actinobacteria. However, the abundance of Campylobacteraceae and Lachnospiraceae was higher in patients with recurrent cancer, whereas Cardiobacteriaceae, Atopobiaceae and Neisseriaceae were more abundant in those without recurrent cancer.
Patients with cancer recurrence also had higher levels of Peptostreptococcus, Campylobacter, Granulicatella, Porphyromonas, Oribacterium, Actinomyces, Corynebacterium, Capnocytophaga and Dialister, whereas those without recurrence had increased abundances of Prevotella, Cardiobacterium, Olsenella, Atopobium, Fusobacterium, Lactobacillus, Streptococcus, Leptotrichia and Parvimonas, the researchers found.
The team also identified pathways linked to bacterial metabolism that were differentially activated in patients with and without recurrent oral cancer, suggesting altered metabolic responses between those groups of patients.
Predicting recurrence
The researchers identified five bacterial signatures that showed the greatest discrimination between the people with and without cancer recurrence: Leptotrichia trevisanii, Capnocytophaga sputigena, Capnocytophaga, Cardiobacterium and Olsenella.
A model that included these microbial signatures predicted the recurrence of oral cancer in an independent group of 46 patients with an accuracy of about 75%, the team found.
“These results suggest that recurrence-related microbial biomarkers could serve as a reliable and noninvasive method for predicting [oral squamous cell carcinoma] recurrence,” the authors say. However, they add, larger studies are needed to confirm the correlation between the oral microbiota and oral cancer recurrence as well as to validate the five microbial biomarkers of cancer recurrence.
