[The microbiome in head and neck tumors-initial findings and outlook]

Technical progress in molecular biology has allowed for a more detailed analysis of the composition of the human microbiome in recent years. Inter- and intraindividual differences in microbiome composition have been demonstrated, which in part correlate with the occurrence of certain diseases. For some of the so-called oncomicrobes, a direct relationship between their effect on the host organism and carcinogenesis has been demonstrated, predominantly for gastrointestinal cancers. Initial results for head and neck cancer show inter- and intraindividual differences in the local microbiota of the tumor environment, with certain bacterial strains over- or underrepresented. Our results confirm these findings, e.g., by showing a relative abundance of fusobacteria in tumor tissue while streptococci were relatively reduced. Currently available results show a high degree of inter- and intraindividual variation, thus requiring larger patient cohorts for functional analyses.