Association between Fusobacterium nucleatum and patient prognosis in metastatic colon cancer

Abstract

Recent evidence suggests thatFusobacterium nucleatum(Fn) is associated with the development and progression of colorectal cancer. We aimed to delineate the clinical implications ofFnin metastatic colon cancer. We performed quantitative polymerase chain reaction (qPCR) using DNA samples from synchronous metastatic colon cancer patients with either formalin-fixed paraffin-embedded (FFPE) archival primary site tumor samples or fresh colon tissues. Progression-free survival (PFS)1 and PFS2 were defined as PFS of first- and second-line palliative settings. qPCR forFnwas successfully performed using 112 samples (FFPE, n = 61; fresh tissue, n = 51). Forty-one and 68 patients had right-sided and left-sided colon cancer, respectively. Patients withFnenriched right-sided colon cancers had shorter PFS1 (9.7 vs. 11.2 months) than the other subgroups (HR 3.54, 95% confidence interval [CI] 1.05–11.99;P = 0.04).Fnpositive right-sided colon was also associated with shorter PFS2 (3.7 vs. 6.7 months; HR 2.34, 95% CI 0.69–7.91;P = 0.04). In the univariate analysis, PFS1 was affected by differentiation andFnpositive right-sided colon cancer. The multivariate analysis showed that differentiation (HR 2.68, 95% CI 1.40–5.14,P = 0.01) andFnpositive right-sided colon (HR 0.40, 95% CI 0.18–0.88,P = 0.02) were associated with PFS1.Fnenrichment in right sided colon was not associated with overall survival (OS).Fnenrichment has significantly worse prognosis in terms of PFS1 and PFS2 in patients with right-sided metastatic colon cancers.