Culturable and unculturable periodontal microorganisms in non-small cell lung cancer: an exploratory analysis

Abstract The impact of the periodontitis-associated microbiota on lung cancer patients remains controversial and poorly explored. This study aims to characterize the periodontal microbiota in saliva and subgingival plaque of patients with non-small cell lung cancer (NSCLC) and healthy volunteers. Twenty-four individuals (12 with NSCLC and 12 healthy controls) were included, matched by age and stage of periodontitis. Periodontal clinical examination, saliva, and subgingival plaque sampling were processed using qPCR techniques to determine culturable and non-culturable periodontopathic microorganisms. Microbiological results revealed differences in saliva samples of NSCLC patients, with a significant decrease in the frequency of Treponema denticola (p = 0.019) and Eubacterium brachy (p = 0.045). Furthermore, a significant reduction was demonstrated in bacterial concentrations of Eubacterium brachy in plaque (p = 0.027) and saliva (p = 0.0076) in NSCLC patients. In contrast, Desulfobulbus oralis showed higher frequency (p = 0.05) and concentration (p = 0.038) in subgingival plaque in these patients. Porphyromonas gingivalis was not associated with NSCLC. Desulfobulbus oralis should be studied as a potential microbiota dysbiosis biomarker in NSCLC. These findings highlight the potential diagnostic value of periodontal microbiota in NSCLC.