Open Access

Mmadili N. Ilozumba, Tengda Lin, Sheetal Hardikar, Doratha A. Byrd, June L. Round, W. Zac Stephens, Andreana N. Holowatyj, Christy A. Warby, Victoria Damerell, Christopher I. Li, Jane C. Figueiredo, Adetunji T. Toriola, David Shibata, Gary C. Fillmore, Bartley Pickron, Erin M. Siegel, Christoph Kahlert, Vaia Florou, Biljana Gigic, Jennifer Ose, Cornelia M. Ulrich

• Background: Cachexia accounts for about 20% of all cancer‐related deaths and indicates poor prognosis. The impact of Fusobacterium nucleatum (Fn), a microbial risk factor for colorectal cancer (CRC), on the development of cachexia in CRC has not been established. Methods: We evaluated the association between Fn abundance in pre‐surgical stool samples and onset of cachexia at 6 months post‐surgery in n = 87 patients with stages I–III CRC in the ColoCare Study. Results: High fecal Fn abundance compared to negative/low fecal Fn abundance was associated with 4‐fold increased risk of cachexia onset at 6 months post‐surgery (OR = 4.82, 95% CI = 1.15, 20.10, p = 0.03). Conclusion: Our findings suggest that high fecal Fn abundance was associated with an increased risk of cachexia at 6 months post‐surgery in CRC patients. This is the first study to link Fn abundance with cachexia in CRC patients, offering novel insights into biological mechanisms and potential management of cancer cachexia. Due to the small sample size, our results should be interpreted with caution. Future studies with larger sample sizes are needed to validate these findings.