Low Yield and High Cost of Gastric and Duodenal Biopsies for Investigation of Symptoms of Abdominal Pain During Routine Esophagogastroduodenoscopy

The spectrum of TP53 mutations in Rwandan patients with gastric cancer

BACKGROUND

Gastric cancer is the sixth most frequently diagnosed cancer and third in causing cancer-related death globally. The most frequently mutated gene in human cancers is TP53, which plays a pivotal role in cancer initiation and progression. In Africa, particularly in Rwanda, data on TP53 mutations are lacking. Therefore, this study intended to obtain TP53 mutation status in Rwandan patients with gastric cancer.

RESULTS

Formalin-fixed paraffin-embedded tissue blocks of 95 Rwandan patients with histopathologically proven gastric carcinoma were obtained from the University Teaching Hospital of Kigali. After DNA extraction, all coding regions of the TP53 gene and the exon-intron boundary region of TP53 were sequenced using the Sanger sequencing. Mutated TP53 were observed in 24 (25.3%) of the 95 cases, and a total of 29 mutations were identified. These TP53 mutations were distributed between exon 4 and 8 and most of them were missense mutations (19/29; 65.5%). Immunohistochemical analysis for TP53 revealed that most of the TP53 missense mutations were associated with TP53 protein accumulation. Among the 29 mutations, one was novel (c.459_477delCGGCACCCGCGTCCGCGCC). This 19-bp deletion mutation in exon 5 caused the production of truncated TP53 protein (p.G154Wfs*10). Regarding the spectrum of TP53 mutations, G:C > A:T at CpG sites was the most prevalent (10/29; 34.5%) and G:C > T:A was the second most prevalent (7/29; 24.1%). Interestingly, when the mutation spectrum of TP53 was compared to three previous TP53 mutational studies on non-Rwandan patients with gastric cancer, G:C > T:A mutations were significantly more frequent in this study than in our previous study (p = 0.013), the TCGA database (p = 0.017), and a previous study on patients from Hong Kong (p = 0.006). Even after correcting for false discovery, statistical significance was observed.

CONCLUSIONS

Our results suggested that TP53 G:C > T:A transversion mutation in Rwandan patients with gastric cancer is more frequent than in non-Rwandan patients with gastric cancer, indicating at an alternative etiological and carcinogenic progression of gastric cancer in Rwanda.

Helicobacter pylori Antimicrobial Resistance Using Next-Generation Sequencing in Stool Samples in a Pediatric Population

Helicobacter pylori ( H pylori ) eradication rates have declined globally, stressing the importance of antimicrobial susceptibility testing to inform treatment. Molecular tests such as next-generation sequencing (NGS) provide susceptibility data for the antibiotics used in the treatment of H pylori in a noninvasive, effective, and rapid manner. We obtained stool susceptibility testing using a novel NGS-based analysis and compared results with the current "gold standard" of gastric biopsy culture via agar dilution in 20 pediatric patients with evidence of H pylori in gastric biopsies. Stool NGS-based antimicrobial susceptibility analysis was highly concordant with agar dilution for no resistance (100% agreement), as well as clarithromycin, levofloxacin, and amoxicillin resistance (100%, 67%, and 100% agreement, respectively) but not concordant for metronidazole in our cohort of patients. Future studies involving a larger number of patients and geographical regions are needed to further validate this analysis.

Real-Time Evaluation of Helicobacter pylori Infection by Convolution Neural Network During White-Light Endoscopy: A Prospective, Multicenter Study (With Video)

INTRODUCTION

Convolutional neural network during endoscopy may facilitate evaluation of Helicobacter pylori infection without obtaining gastric biopsies. The aim of the study was to evaluate the diagnosis accuracy of a computer-aided decision support system for H. pylori infection (CADSS-HP) based on convolutional neural network under white-light endoscopy.

METHODS

Archived video recordings of upper endoscopy with white-light examinations performed at Sir Run Run Shaw Hospital (January 2019-September 2020) were used to develop CADSS-HP. Patients receiving endoscopy were prospectively enrolled (August 2021-August 2022) from 3 centers to calculate the diagnostic property. Accuracy of CADSS-HP for H. pylori infection was also compared with endoscopic impression, urea breath test (URT), and histopathology. H. pylori infection was defined by positive test on histopathology and/or URT.

RESULTS

Video recordings of 599 patients who received endoscopy were used to develop CADSS-HP. Subsequently, 456 patients participated in the prospective evaluation including 189 (41.4%) with H. pylori infection. With a threshold of 0.5, CADSS-HP achieved an area under the curve of 0.95 (95% confidence interval [CI], 0.93-0.97) with sensitivity and specificity of 91.5% (95% CI 86.4%-94.9%) and 88.8% (95% CI 84.2%-92.2%), respectively. CADSS-HP demonstrated higher sensitivity (91.5% vs 78.3%; mean difference = 13.2%, 95% CI 5.7%-20.7%) and accuracy (89.9% vs 83.8%, mean difference = 6.1%, 95% CI 1.6%-10.7%) compared with endoscopic diagnosis by endoscopists. Sensitivity of CADSS-HP in diagnosing H. pylori was comparable with URT (91.5% vs 95.2%; mean difference = 3.7%, 95% CI -1.8% to 9.4%), better than histopathology (91.5% vs 82.0%; mean difference = 9.5%, 95% CI 2.3%-16.8%).

DISCUSSION

CADSS-HP achieved high sensitivity in the diagnosis of H. pylori infection in the real-time test, outperforming endoscopic diagnosis by endoscopists and comparable with URT. Clinicaltrials.gov ; ChiCTR2000030724.

Lessons From a Quality Improvement Project to Standardize the Process of Gastric Biopsy Culture for Helicobacter pylori

Despite expert recommendations, clinician's adherence to pediatric societal clinical practice guidelines is variable, particularly with respect to the use of gastric biopsy culture in the initial diagnosis of Helicobacter pylori infection. In addition, the implementation of routine use of gastric biopsy culture has been challenging with several factors affecting the rate of successful primary H pylori culture.

Methods

We conducted a quality improvement (QI) project with the aims of increasing the rate of successful primary culture. The QI project involved educational efforts among our gastroenterologists, endoscopy suite personnel, and laboratory personnel. We compared the frequency of gastric biopsy culture sent in patients with international classification of diseases 9th revision code 041.86, and 10th revision codes B96.81 evaluated by pediatric gastroenterologists at Boston Children's Hospital during the 9 months before the QI intervention (February 1, 2019 to October 31, 2019) and 9 months after the QI intervention (November 1 2019 to July 31 2020). We also compared the rate of culture growth in patients with positive histology (culture positivity), and antimicrobial susceptibilities before and after November 1, 2019.

Results

We observed an increased frequency of gastric biopsy acquisition by any gastroenterologist, obtained in 39% (28 of 71) preintervention patients compared with 67% (36 of 54) intervention patients (P = 0.004). There was an increase in the percentage of culture positivity across study periods from 21% (3 of 14) preintervention to 45% (5 of 11) postintervention (P = 0.39; 95% confidence interval, 0.64-7.00).

Conclusion

Educational initiatives and collaborative work with staff physicians, endoscopy personnel, and hospital laboratory appear to be effective tools to increase usage of gastric biopsy culture as a diagnostic tool for H pylori infection and to increase culture positivity. Improving the surveillance of local resistance rates will improve the selection of the most effective primary treatment in specific geographic areas.

Do Low-Risk Patients With Dyspepsia Need a Gastroscopy? Use of Gastroscopy for Otherwise Healthy Patients With Dyspepsia

Background

Choosing Wisely Canada (CWC) recommends not to perform gastroscopy for dyspepsia in otherwise healthy adults less than 55 years of age (2014). The aim of this study was to evaluate the use of gastroscopy in a young, healthy population with uncomplicated dyspepsia.

Methods

A retrospective review of gastroscopies completed during 3-month periods in 2015, 2016, and 2017 identified all patients undergoing gastroscopy for the primary indication of dyspepsia. Low-risk patients for dyspepsia were defined as adults, aged 18 to 54 years without alarm symptoms, comorbidities and/or abnormal imaging findings or laboratory values. Gastroscopy and pathology reports were reviewed to identify clinically actionable findings. Clinical outcomes were followed to December 31, 2018 including gastroenterology referrals, emergency room visitation and hospitalization.

Results

Among 1358 patients having a gastroscopy for dyspepsia, 480 (35%) were low-risk patients. Sixteen patients 3.3% (16/480) had a clinically actionable result found on gastroscopy or biopsy. No malignant lesions were detected. Low-risk patients were followed up for an average of 2.75 years, 8% (39/480) visited the emergency department (ED), 1% (3/480) of patients were admitted to hospital and 12% (59/480) of patients were re-referred for a dyspepsia-related concern.

Interpretation

A high rate of low yield, high cost, invasive endoscopic investigations were performed in this population of otherwise healthy patients under age 55 years. These data suggest limited uptake of current recommendations against the routine use of gastroscopy to investigate dyspepsia.

Reassessing the value of gastroscopy for the investigation of dyspepsia

OBJECTIVE

To evaluate the diagnostic yield of investigating dyspepsia with oesophagogastroduodenoscopy (OGD) with or without mucosal biopsy.

DESIGN

Retrospective service evaluation study.

SETTING

Two teaching hospitals: The Royal Hallamshire Hospital and Northern General Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, UK.

PATIENTS

500 patients, 55 years of age and over, who underwent OGD to investigate dyspepsia were included. The study period included a 3-month window. All OGDs were performed on an outpatient basis.

INTERVENTIONS

Data were extracted from electronic OGD records within the study period.

MAIN OUTCOME MEASURES

Diagnostic yield provided by endoscopic examination and histological assessment.

RESULTS

378 patients (75.6%) were reported to have some form of endoscopic abnormality, and 417 patients (83.4%) had biopsies taken. The most common findings at OGD were gastritis (47.2%) and oesophagitis (24.4%). Oesophagogastric malignancy was seen in 1%. Diagnoses made endoscopically or histologically that would not have been appropriately managed by empirical therapies were seen in 16.2%.

CONCLUSION

OGD in dyspepsia influences patient management in approximately one-sixth of cases. However, the majority of patients are sufficiently managed with Helicobacter pylori testing and eradication and/or a trial of proton pump inhibitor therapy. Further non-invasive approaches are needed to identify patients who need endoscopy for biopsy or therapy.