- Article
Prevalence and Impact on Quality of Life of Small Intestinal Bacterial Overgrowth (SIBO)-Related Symptoms in Patients with Upper Gastrointestinal Cancer
- Rosa Rosania,
- Achim J. Kaasch and
- Katrin Bose
- + 5 authors
Introduction: Although patients with upper gastrointestinal (GI) cancer have an increased risk of developing small intestinal bacterial overgrowth (SIBO) due to disease- and treatment-related factors, SIBO remains underdiagnosed in oncology. Aim and Methods: This prospective study evaluated the prevalence of SIBO and its impact on symptom-related quality of life (QoL) in patients with current or prior upper GI cancer. Between April 2021 and May 2022, patients reporting SIBO-related symptoms like bloating and/or diarrhea completed a standardized symptom questionnaire. QoL impact was scored from 0 (none) to 3 (severe). Patients with scores > 1 and no recent antibiotic use underwent upper endoscopy with duodenal aspirate. SIBO was defined as >103 CFU/mL. Results: Ninety patients were enrolled (51% female; median age of 65 years): 35% had pancreatic, 34% gastric, 17% biliary, and 14% esophageal cancer. Sixty reported SIBO-related symptoms: 35% reported bloating, 11% diarrhea, and 54% both. Of these, 36 underwent endoscopy; 53% were diagnosed with SIBO. Among SIBO-positive patients, 95% reported bloating and 58% reported diarrhea. Prior abdominal surgery was recorded in 63% of SIBO cases. Conclusions: SIBO was identified in more than half of symptomatic upper GI cancer patients, with a strong association with bloating and previous abdominal surgery. These findings emphasize the importance of clinical awareness and appropriate diagnostic evaluation for SIBO in this high-risk group to improve symptom control and quality of life.
13 December 2025





