Validation of the Association Between the Abundance of Three Bacterial Genera in Stool Samples and the Risk of Gallbladder Cancer in South American Patients With Gallstones

NCT07635745 | Completed

• 1 other identifier: 2026-010
• Study Type: observational
• Target: 120
• Locations: 4 countries
• Sites: 4

Brief Summary

In our previous work, we found three types of bacteria in stool samples from South American patients with gallstones linked to a higher risk of gallbladder cancer. The aim of the present study is to confirm these associations using a separate set of South American stool samples.

Conditions

Gallbladder Malignant Neoplasm

Outcome Measures

Primary Outcomes (1)

• Validation of the Association Between Gallbladder Cancer Risk in South American Patients With Gallstones and the Centered Log-Ratio-Transformed Abundance of Three Stool Bacterial Genera Determined by Shotgun Metagenomic Sequencing

  Baseline

Study Arms (2)

South American patients with gallbladder cancer

South American patients with gallstones, with no evidence of gallbladder cancer upon pathological ex

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

\- Patients with gallstones and cancer-free OR - Patients with gallbladder cancer

You may qualify if:

• Patients with gallstones and cancer-free OR - Patients with gallbladder cancer

You may not qualify if:

• Antibiotics use

Sponsors & Collaborators

• Centre Paul Strauss: lead
• Statistical Genetics Research Group, Institute of Medical Biometry and Informatics, Heidelberg University of Heidelberg: collaborator

Study Sites (4)

Caja Nacional de Seguro Social Cochabamba, Complejo Hospitalario Viedma, Instituto Gastroenterológico

Cochabamba, Bolivia

Location

Hospital Dr. Hernán Henriquez Aravena, Complejo Asistencial Padre las Casas, Hospital Regional de Talca, Hospital Regional de Concepción, Hospital Regional de Arica

Talca, Chile

Location

Statistical Genetics Research Group, Institute of Medical Biometry, University of Heidelberg

Heidelberg, Germany

Location

Instituto Regional de Enfermedades Neoplasicas del Sur (IREN SUR), Hospital Regional Honorio Delgado Espinoza, Hospital Goyeneche Arequipa, Hospital Regional Manuel Nuñez Butron-Puno

Arequipa, Peru

Location

Related Links

• Related Info

Biospecimen

Retention: SAMPLES WITH DNA

The aim of the study is to validate the three identified associations using an independent set of South American stool samples (n=40 from GBC and n=80 from gallstone disease patients). DNA extracted from the faecal samples will be pre-processed using Illumina DNA prep 1/4 for library preparation and sequenced on a NovaSeq X 25B 300c lane machine. Raw data will be pre-processed following a cleaning protocol with bbduk (bbmap-version 38.93). Cleaned reads will be analysed using the PathSeq pipeline in GATK (v4.1.6.0). Reads aligning to the human reference genome (GRCh38) will be removed, and remaining reads will be mapped to microbial reference databases obtained from the European Molecular Biology Laboratory (EMBL-Broad Institute). Analyses will be performed using established reference sets and default parameters, with a minimum clipped read length of 50. Microbiome data will be analyzed using the R phyloseq framework. Batch effects will be assessed through Bray-Curtis distances

MeSH Terms

Conditions

Gallbladder Neoplasms

Condition Hierarchy (Ancestors)

Biliary Tract Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Biliary Tract Diseases; Digestive System Diseases; Gallbladder Diseases

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Target Duration: 1 Day
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 11, 2026
• First Posted: June 9, 2026
• Study Start: December 1, 2019
• Primary Completion: January 31, 2026
• Study Completion: January 31, 2026
• Last Updated: June 9, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will share

Locations

CL (1); BO (1); PE (1); DE (1)