Changes in the microbial flora on the oral mucosa after cancerous alteration may lead to both local and systemic infections. Researchers from India assessed the microbial flora associated with the surfaces of oral squamous cell carcinoma and compared the oral microbial contents with healthy mucosa. They also assessed the microbial flora from the saliva culture in subjects with oral squamous cell carcinoma and healthy controls.
The study included 30 subjects with oral squamous cell carcinoma and 30 healthy matched controls. The investigators found that oral squamous cell carcinoma sites harbor significantly more bacteria and yeasts compared to the control group. The microbial flora predominantly isolated from the carcinoma site were Streptococcus, Staphylococcus, Moraxella, Klebsiella, Citrobacter, Proteus, and Pseudomonas spp., Enterococcus feacalis, and Candida albicans. The median number of colony forming units (CFU)/mL at carcinoma sites (3.85 x 105 CFU/mL) was significantly higher than that of the healthy mucosa (0.571 x 105 CFU/mL) Similarly, in saliva of carcinoma subjects, the median number of CFU/mL (2.408 x 105 CFU/mL) was significantly higher than that of saliva in control subjects (0.78 x 105 CFU/mL)
The study clearly indicates that the subjects with oral squamous cell carcinoma harbor significantly more microbial flora. The study's implications are that emphasis has to be made to prevent changes in the microbial flora of the oral cavity. This can be achieved by reducing sugar intake, using probiotics when indicated, avoiding unnecessary use of antibiotics, and maintaining good dental and oral hygiene.
Microscopic view of oral bacteria and yeast