Prognostic and clinicopathological significance of Fusobacterium nucleatum in colorectal cancer: a systemic review and meta-analysis

Background: Fusobacterium nucleatum has been identified to promote tumor progression in colorectal cancer (CRC). However, asso-ciation between F. nucleatum and prognostic or clinicopathological features has been diverse among studies, which could be affected by type of biospecimen (formalin-fixed paraffin-embedded or fresh frozen [FF]). Methods: Articles were systemically reviewed for studies that included the correlation between F. nucleatum and prognosis or clinicopathological features in CRC. Results: Ten arti-cles, eight studies with survival-related features involving 3,199 patients and nine studies with clinical features involving 2,655 pa-tients, were eligible for the meta-analysis. Overall survival, disease-free survival, and cancer-specific survival were all associated with worse prognosis in F. nucleatum-high patients (p < .05). In subgroup analysis, only studies with FF tissues retained prognostic signifi-cance with F. nucleatum. In meta-analysis of clinicopathological variables, F. nucleatum level was associated with location within co-lon, pT category, MLH1 hypermethylation, microsatellite instability status, and BRAF mutation regardless of type of biospecimen. However, lymph node metastasis and KRAS mutation was only associated with F. nucleatum level in FF-based studies. Conclusions: In conclusion, type of biospecimen could affect the role of F. nucleatum as a biomarker associated with clinicopathological features and prognosis.