Intestinal Microbiome After Gastrectomy

Study Overview
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Brief Summary
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The gastric barrier plays a major role in the maintanance of the distal intestinal microbiome composition. It has been shown before that the use of gastric acid suppression medication, such as proton pump inhibitors, are associated with distinctive alterations of the intestinal microbiome. Foremost, the invasion of predominantly oral bacteria, like Veillonella and Streptococcus species, were a resurring finding in previous reports. Gastric cancer treatment includes the total or subtotal resection of the stomach which can influence the gastric acid production. However, the influence by alterations in gastric milieu after this treatment on the composition of the intestinal microbiome is not well studied. Therefore, the intestinal microbiome of patients after total or subtotal gastrectomy and its influence on intestinal inflammation and gut permeability will be studied.

Official Title
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Surgical Gastric Cancer Treatment: Influence on Intestinal Microbiome

Conditions
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Gastric Cancer

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age 18 years and above history of radical removal of gastric cancer (Test group and Control group 1) or PPI (Control group 3) informed consent Exclusion Criteria: chemotherapy or radiotherapy 12 months prior to inclusion gastric stump cancer usage of antibiotics, pro- pre or synbiotics, H2-blocker 1 month prior to inclusion PPI use (except for Control group 3) 1 month prior to inclusion history of radical removal of gastric cancer (Control group 2-3) history of gastrointestinal tract resections (other than gastric) recurrence of gastric cancer current non-gastric malignancies

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Test group<br>Patients who underwent total or subtotal gastrectomy for the treatment of gastric cancer | |
| Control group 1<br>Patients who underwent endoscopic mucosal resection/submucosal dissection for the treatment of gastric cancer | |
| Control group 2<br>In-house relatives of Test group and Control group 1 participants | |
| Control group 3<br>Patients with long-term history of proton pump inhibitor usage | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intestinal microbiome composition | Significant differences in the beta-diversity of the intestinal microbiome between Test group and Control groups | 5 years after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intestinal microbiome composition (II) | Significant differences in the alpha-diversity of the intestinal microbiome between Test group and Control groups | 5 years after surgery | 
| Fecal calprotectin | Significant differences in intestinal inflammation measured by fecal calprotectin between Test group and Control groups | 5 years after surgery | 
| Fecal zonulin | Significant differences in intestinal permeability measured by fecal zonulin between Test group and Control groups | 5 years after surgery | 
| Serum LPS | Significant differences in serum LPS between Test group and Control groups | 5 years after surgery | 
| Serum sCD14 | Significant differences in serum sCD14 between Test group and Control groups | 5 years after surgery | 
| Serum LBP | Significant differences in serum LBP between Test group and Control groups | 5 years after surgery | 
| Serum sCD163 | Significant differences in serum sCD163 between Test group and Control groups | 5 years after surgery | 
| Serum sMR | Significant differences in serum sMR between Test group and Control groups | 5 years after surgery | 
| Serum CRP | Significant differences in serum CRP between Test group and Control groups | 5 years after surgery | 
| Serum DAO | Significant differences in serum DAO between Test group and Control groups | 5 years after surgery |