NCT06349590 · University of Chicago
Manipulation of the Gut Microbiome by a Standardized Preoperative Diet to Prevent Colorectal Cancer Recurrence and Metastasis Following Surgery
(DIET)
What this study is about
A single treatment group$1, forward-looking, single center Phase1/2 Dietary intervention trial for subjects diagnosed with colorectal cancer and scheduled for tumor resection more than 21 days from informed consent. Subjects will be provided 21 days of standardized High-fiber/low-fat meals and complete a food diary up until lunch on the day prior to surgery.
View original scientific description
A single arm, prospective, single center Phase1/2 Dietary intervention trial for subjects diagnosed with colorectal cancer and scheduled for tumor resection more than 21 days from informed consent. Subjects will be provided 21 days of standardized High-fiber/low-fat meals and complete a food diary up until lunch on the day prior to surgery. Blood samples will be collected at baseline and on the day of surgery. Stool samples will be collected throughout the dietary intervention period at specific timepoints, on the day of surgery, and 30 days post-surgery. Tissue from the tumor resection will be isolated for organoid cultures. Subjects will be followed per standard of care for up to 5 years or disease recurrence, whichever comes first. Subject may be treated for their cancer prior to surgery and/or during the follow-up period.
Interventions
DIETARY_SUPPLEMENT
High-fiber/low-fat meals
Meals with Low fat/High fiber
Primary outcome measures
Change in lab values of the dietary intervention on the collagenolytic potential of the microenvironment.
Time frame: At baseline on Day 1 until final values collected on 6 months post-op visit.
To assess whether the dietary intervention significantly changed the collagenase activity, the site will compare each subject's baseline and final values.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Must have histologically or cytologically confirmed colorectal adenocarcinoma.
- Planned for primary tumor resection at the University of Chicago Medicine ≥21 from date of obtained informed consent. Patients with metastatic disease but undergoing primary site resection are eligible for the study.
- Age ≥18 years.
- Patients \<18 years of age, children are excluded from this study, because they have unique nutritional requirements that might not be met by with the standardized diet. The food in the diet is designed for adults and would not be feasible for children, especially those attending school. In addition, colon cancer is extremely rare in children.
- May have received neoadjuvant therapy (chemotherapy, radiation).
- Patients with Hepatic arterial infusion (HAI) pumps are considered eligible.
- Ability to understand and willing to sign an informed consent, participate in the dietary intervention, collect stools, donate blood, and complete a pre-nutritional evaluation and compliance/patient satisfaction survey.
Exclusion criteria
- Previous ostomy (ileostomy or colostomy) or definitive plan for an ostomy (ileostomy or colostomy) during the procedure.
- Antibiotic exposure within 60 days before diet initiation. Antibiotic exposure is defined as a 'course of treatment to treat an infection'. Prophylactic antibiotics prior to a procedure is okay.
- Prebiotic/Probiotic exposure within 60 days before diet initiation.
- Concomitant separate malignancy.
- Allergy to perioperative medications (oral neomycin/metronidazole for bowel preparation, intraoperative prophylactic intravenous cefazolin and metronidazole).
- Patients who are pregnant are not eligible for the study. Pregnant women are excluded from this study because the preoperative diet is not specifically formulated to meet the specific nutritional requirements during the prenatal period.
- History of inflammatory bowel disease
- Severe food allergies precluding the ability to tolerate the standardized dietary intervention.
- Patients with uncontrolled intercurrent illness
Where
- Chicago, Illinois
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Nov 5, 2025 · Source of record for eligibility and locations