Prognostic impact of Fusobacterium nucleatum on survival in colorectal cancer: A systematic review and meta-analysis

Recent studies have demonstrated a significant correlation between Fusobacterium nucleatum (F. nucleatum) and colorectal cancer. However, the prognostic significance of this microorganism in patients with colorectal cancer remains unclear. This meta-analysis aimed to evaluate the impact of F. nucleatum on the overall survival of patients with colorectal cancer. A thorough literature search of PubMed, Embase, and Cochrane Library databases was conducted until December 2023. The hazard ratio (HR) with the corresponding 95% confidence interval (CI) was analyzed using Review Manager 5.4 software for survival outcomes, including the overall survival (OS). A total of 13 studies, covering 4475 samples with colorectal cancer, were selected based on specified inclusion and exclusion criteria. In the univariate and multivariate analyses, patients with positive or high abundance of Fusobacterium in the cancer tissues displayed poorer OS (univariate HR = 1.28, 95% CI: 1.08-1.53, P = 0.006; multivariate HR = 1.61, 95% CI: 1.37-1.88, P < 0.0001) than those with negative/low bacteria levels. Subgroup analysis revealed that Fusobacterium in cancer tissues was associated with tumor stage and differentiation. Patients with stage III and IV, T3 and T4, or poorly differentiated tumors had a higher abundance of Fusobacterium in cancer tissues than those with stage I and II, T1 and T2, or well-to-moderately differentiated tumors (P < 0.05). No statistically significant difference in lymph node metastasis was observed. These findings suggest that the Fusobacterium microbiome may play a significant role in predicting the survival outcomes in patients with colorectal cancer.