Fusobacterium in resectable colorectal cancer predicts recurrence and chemotherapy response

First results from the multicenter FUSOMAP project show that intratumoral Fusobacterium is present in 21% of resectable colorectal cancer tumors and identifies a more aggressive disease subtype with a higher recurrence risk. The study, published in ESMO Open and led by VHIO, found Fusobacterium-positive tumors had weaker immune responses and showed no significant benefit from adjuvant chemotherapy, unlike Fusobacterium-negative tumors. Stool analysis detected the bacterium up to three years before relapse. The findings, based on 740 patients across nine Spanish hospitals, suggest Fusobacterium could serve as a biomarker for personalized treatment and surveillance, though prospective validation in larger cohorts is needed before clinical application.