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 …