Bacterial Intestinal Gut Modification Around Cancer Surgery (BIG MACS) Diet

Early Phase 1

Completed

• Conditions: Dysbiosis; Sarcopenia; Colon Cancer
• Interventions: Dietary Supplement: Standard Diet; Dietary Supplement: BIG MACS Diet

• Registration Number: NCT05658263
• Lead Sponsor: University of Minnesota

Brief Summary

The long-term study objective is to develop optimized nutritional therapies for surgery and test them in clinical practice. This pilot study will test a microbiome-optimization diet in colorectal cancer surgery patients. The study hypothesizes that the Bacterial Intestinal Gut Modification Around Cancer Surgery (BIG MACS) Diet will provide participants with increased microbiota accessible carbohydrates (MACs) to support the microbiome and improve outcomes.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2022-10-11
• Study First Submitted QC: 2022-12-19
• Study First Posted: 2022-12-20
• Study Start: 2023-01-03
• Primary Completion: 2024-08-15
• Study Completion: 2024-08-15
• Status Verified: 2025-05
• Last Update Submitted: 2025-05-12
• Last Update Posted: 2025-05-13

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 24

Inclusion Criteria

• Age 25-70 years
• Primary diagnosis of colon cancer, stages 1-3.
• Able and willing to provide informed consent.
• English-speaking.
• Willingness to return to the study site for specified study visits at D7 and D30.
• Able to comply with study measures.

Exclusion Criteria

• Age ≤ 25 years or ≥70 years
• If surgery is being performed for any reason other than resection of colon cancer. Neoadjuvant therapy, or if surgery is not the initial approach for the patient's colon cancer treatment
• Significant anemia (hemoglobin 1.0 g/dL or more below normal range) or history of coagulopathy: any personal history of hereditary or acquired bleeding disorder, or thrombocytopenia with platelets under 100,000.
• Serum creatinine greater than 1.5 mg/dL.
• Serum total bilirubin greater than the upper limit of normal in the absence of Gilbert's syndrome or alkaline phosphatase or ALT or AST greater than 2.5 times the upper limit of normal. Elevated INR (1.5 or above).
• Alcohol intake more than one drink or greater than 20 grams per day for women or 30 grams per day for men.
• History of gastrointestinal surgery including stomach, small bowel or colon resection, pancreatic surgery, bile duct or gallbladder surgery, or splenectomy, or gastric bypass.
• History of intra-abdominal sepsis.
• Previous organ transplantation.
• Self-reported HIV-positive status, active tuberculosis, active malaria, chronic hepatitis B or C, cirrhosis, or inflammatory bowel disease.
• Currently pregnant or nursing.
• History of alcohol, drug, or opioid dependency (excluding nicotine) in the past five years.
• Active psychosocial or psychiatric problem that is likely to interfere with adherence to the protocol.
• Depression: A CES-D score more than 16 and a psychologist determining that the patient is not a good fit for surgery.
• Body mass index (BMI) <20 or > 40 kilograms per meter squared:

obesity is known to impact the microbiome and immune system and the occurrence of anastomotic leak, and extreme obesity may confound interpretation of these factors in association to leak. Inferences may be made by matching participants with less severe obesity (BMI <40).

• Presence of any type of non-MRI compatible implant, including cardiac pacemakers or defibrillators, neurostimulators, cochlear implants, or other metallic hardware
• Self-reported history of claustrophobia.
• Incarceration
• Inability to adhere to the study protocol, procedures, and diet
• Exclusions may also be made at the discretion of the attending physician.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Standard Diet	Standard Diet	Participants receiving only standard of care (SOC) nutrition advice, which is SOC Dietary Instructions, as provided by routine surgical consults and one protein shake per day for 4 weeks prior to surgery (SOC).
BIG MACS Diet	BIG MACS Diet	Participants will be instructed to consume the study diet, referred to as the 'BIG MACS Diet' and one protein shake per day for 4 weeks prior to surgery (SOC). Following surgery, participants will continue to follow the BIG MACS Diet for an additional four weeks, with solid food reintroduction after surgery as early as tolerated.

Primary Outcome Measures

Name	Time	Method
Change in muscle mass	baseline and 4 weeks after surgery	The change in muscle mass assessed by MRI-measured area and density of the psoas muscle at the level of the L3 vertebra with adjunct grip strength measurement.
Frequency of accidental mucus leakage	4 weeks after surgery	this will be assessed in times per day or times per month
stool consistency	4 weeks after surgery	Bristol Stool Chart: Type 1 (hard lumps) through Type 7 (watery, no solid pieces, entirely liquid
Laxative/stool softener use	24 hours before surgery	range; 0-4+ doses
Bowel emptying patterns	24 hours before surgery	includes constipation, diarrhea, urgency; range: 0 (never) --\> 4 (always)
Frequency of accidental gas leakage	4 weeks after surgery	this will be assessed in times per day or times per month
Gastrointestinal comfort	24 hours before surgery	range: 0 (no problem) --\> 4 (very strong discomfort)
Compliance with the dietary intervention or standard of care- Baseline veggie meter	postop day 30	carotenoid score, triplicate measurement; range: 0 (lower estimated value)-800 (arbitrary units; higher estimated value correlates with greater carotenoid concentrations
Frequency of accidental liquid stool leakage	4 weeks after surgery	this will be assessed in times per day or times per month
Frequency of bowel movements	4 weeks after surgery	this will be assessed in numbers per day or numbers per week
Compliance with the dietary intervention or standard of care- survey	4 weeks	24-hour diet recall surveys conducted by Nutrition Coordinating Center at University of Minnesota

Secondary Outcome Measures

Name	Time	Method
Change in microbiome features- beta diversity	Baseline, time of surgery, postop day 7 and 30	compositionally corrected Aitchison's distances
Change in microbiome features- alpha diversity	Baseline, time of surgery, postop day 7 and 30	Shannon, Simpson, and Chao1 indices
Fecal inflammatory markers	Baseline and 4 weeks after surgery	ELISA. Fecal calprotectin and IgA levels will be measured using ELISA as markers of intestinal inflammation.
Changes in body composition- liver fat	Baseline, time of surgery, postop day 7 and 30	MRI-measured liver fat content
Fecal metabolites	baseline and 4 weeks after surgery	Targeted fecal and serum metabolomics will measure changes in short chain fatty acids (SCFAs) and bile acids.
Changes in body composition- abdominal muscle	Baseline, time of surgery, postop day 7 and 30	total abdominal muscle area in cm squared. Absolute and relative change in total abdominal muscle area per patient over time (cm squared ), with the average change per patient group compared between study and control group
Changes in body composition- psoas muscle	Baseline, time of surgery, postop day 7 and 30	total psoas muscle area in cm squared. Absolute and relative change in total psoas muscle area per patient over time (cm squared ), with the average change per patient group compared between study and control group
Changes in body composition- volume of fat	Baseline, time of surgery, postop day 7 and 30	MRI-measured area (cm2) and volume (L) of subcutaneous and visceral adipose tissue

Trial Locations

Locations (1)

University of Minnesota; 🇺🇸 Minneapolis, Minnesota, United States