Helicobacter Pylori Infection Prevalence and Histopathologic Findings in Laparoscopic Sleeve Gastrectomy

Histopathological Examination of 404 Sleeve Gastrectomy Specimens at a Large UK Center and Systematic Review of the Published Literature

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) specimens are histologically analyzed to identify incidental pathologies. However, no guidelines recommend routine histology. This study evaluates the clinical utility of LSG sample analysis and if incidental diagnoses have a significant clinical impact.

METHODS

A single high-volume UK bariatric unit retrospectively gathered LSG data covering a 9-year period. All specimens were sent for histological analysis. Where incidental diagnoses were identified, patient records were reviewed to assess any clinical management alterations. A systematic review (2013-2023) was performed, exploring rates of incidental pathologies post-LSG. Publications were stratified into those performing routine pre-operative endoscopy, or not, and results compared to present data.

RESULTS

From 01/06/2013 to 12/12/2022, 404 patients underwent LSG. 365/404 (90.4%) had no pathology on histopathological analysis. Seven (1.7%) appeared macroscopically abnormal, with histology identifying 3 polyposis and 1 each of GIST, pernicious anaemia, sarcoidosis and gastritis. Ten (2.48%) appeared macroscopically normal but had incidental pathology. All patient management remained unchanged. Twenty-two (5.44%) were H. pylori positive. Forty-eight publications within wider literature reviewed LSG specimen histology. Fifteen, including 9662 patients undergoing pre-operative endoscopy, found pathological diagnoses in 0.5% and 1 malignancy. Thirty-three studies reporting 17,008 patients without pre-operative endoscopy identified pathologies in 0.45% and 7 malignancies.

CONCLUSION

There is little clinical utility in analyzing macroscopically normal gastric samples following LSG. The potential financial and environmental savings from limiting this practice are of great importance to worldwide bariatric teams. The authors recommend selectively sending LSG specimens only if abnormal gastric mucosa is identified when examining the extracted specimen.

Helicobacter Pylori Infection as the Predominant High-Risk Factor for Gastric Cancer Recurrence Post-Gastrectomy: An 8-Year Multicenter Retrospective Study

Purpose

The reappearance of gastric cancer, a frequent postoperative complication following radical gastric cancer surgery, substantially impacts the near-term and far-reaching medical outlook of patients. The objective of this research was to create a machine learning algorithm that could recognize high-risk factors for gastric cancer recurrence and anticipate the correlation between gastric cancer recurrence and Helicobacter pylori (H. pylori) infection.

Patients and Methods

This investigation comprised 1234 patients diagnosed with gastric cancer, and 37 characteristic variables were obtained. Four machine learning algorithms, namely, extreme gradient boosting (XGBoost), random forest (RF), k-nearest neighbor algorithm (KNN), and multilayer perceptron (MLP), were implemented to develop the models. The k-fold cross-validation technique was utilized to perform internal validation of the four models, while independent datasets were employed for external validation of the models.

Results

In contrast to the other machine learning models, the XGBoost algorithm demonstrated superior predictive ability regarding high-risk factors for gastric cancer recurrence. The outcomes of Shapley additive explanation (SHAP) analysis revealed that tumor invasion depth, tumor lymph node metastasis, H. pylori infection, postoperative carcinoembryonic antigen (CEA), tumor size, and tumor number were risk elements for gastric cancer recurrence in patients, with H. pylori infection being the primary high-risk factor.

Conclusion

Out of the four machine learning models, the XGBoost algorithm exhibited superior performance in predicting the recurrence of gastric cancer. In addition, machine learning models can help clinicians identify key prognostic factors that are clinically meaningful for the application of personalized patient monitoring and immunotherapy.

A comparison of staining methods for Helicobacter pylori in laparoscopic vertical sleeve gastrectomy resections

BACKGROUND

Helicobacter pylori is an important public health concern due to its status as a carcinogenic bacterium. Well adapted to the acidic environment of the human stomach, the variety of strains and virulence factors of the organism when interacting with the host immune system creates an individualistic response. Although estimates suggest that approximately half of the global population is infected with H pylori, the majority of infected persons remain asymptomatic while harboring an increased risk of intestinal metaplasia and gastric cancers. Therefore, appropriate diagnostic testing protocols are imperative.

METHODS

This study compared labeling methodologies, including Wright stain, alcian yellow toluidine blue (AYTB), and immunohistochemistry (IHC) on formalin-fixed paraffin-embedded stomach resections from sleeve gastrectomy patients, to detect H pylori infection.

RESULTS

Although all 3 labeling methods evidenced similar specificity in H pylori detection, the IHC method was significantly more sensitive. However, the IHC cost per test was approximately 5-fold higher than that of the Wright or AYTB stains, and the technical time required per test was at least 6-fold that of Wright or AYTB.

CONCLUSION

Despite the higher cost per test, IHC is the most sensitive and preferred method for determination of H pylori infection.

Frequency of Clinically Significant Findings in the Surgical Pathology Specimen Following Laparoscopic Sleeve Gastrectomy and Concordance with Preoperative Endoscopy: Insights from a Large Single-Center Experience

INTRODUCTION

Endoscopy prior to bariatric surgery is not always performed, and in sleeve gastrectomy (SG), the surgical specimen is not always sent for pathological examination. There is limited data on the frequency of clinically significant findings in SG specimens or correlation with preoperative endoscopy.

METHODS

We reviewed 426 consecutive SG patients to determine the concordance of preoperative endoscopy findings in patients with clinically significant postoperative pathology.

RESULTS

Preoperative endoscopy was performed on 397 patients (93.2%). Three hundred seventy-three patients had preoperative endoscopy and surgical pathology results available. Then, 20/373 (5.4%) patients had potentially significant postoperative pathology, including intestinal metaplasia, autoimmune metaplastic atrophic gastritis (AMAG), gastrointestinal stromal tumors, and/or gastric cancer. The overall incidence of AMAG in the entire cohort was 2.3%. Preoperative gastric biopsies (to include gastric body) identified AMAG in nearly 1/2 of patients. Patients with clinically significant postoperative pathology results had a median [interquartile range] of 3 [3-5] tissue blocks examined as compared to 3 [1-3] for the remainder of the cohort (p < 0.001).

CONCLUSION

This is one of the largest studies describing clinically significant postoperative pathology after SG. AMAG, in particular, is of particular importance as it is associated with a 3-fivefold increase in risk for gastric cancer. The incidence of significant postoperative pathology in this population is small but potentially clinically significant and requires validation in larger studies. We recommend wider sampling in preoperative endoscopy (body and antrum), especially in patients being planned for gastric bypass, consideration for routine pathological examination of SG surgical specimens, with careful gross examination and targeted sampling.

The presence of H. pylori in laparoscopic sleeve gastrectomy specimens is associated with increased mucosal thickness, presence of secondary follicles, increased chronic inflammation, and intestinal metaplasia

Helicobacter pylori is putatively present in over half of the global human population and is recognized as a carcinogenic agent that increases the likelihood of infected patients developing gastric adenocarcinoma or gastric lymphoma. Although there are several means for testing for H. pylori, the gold standard remains the invasive histologic evaluation. The current most popular form of bariatric surgery is the laparoscopic sleeve gastrectomy (LSG) and is the only bariatric surgery which supplies a specimen for histologic evaluation. While non-invasive testing is effective in diagnosing and monitoring H. pylori infection, histological examination of biopsies and resections is the only way to grade chronic inflammation and evaluate specimens for additional pathologies such as intestinal metaplasia. The investigators evaluated 203 sequential LSG specimens collected from a major metropolitan hospital over the period of one year. Specimens were processed to paraffin, stained with hematoxylin and eosin, alcian blue, and immunohistochemistry to determine the presence of H. pylori, chronic inflammation, presence of secondary lymphoid follicles in the mucosa, mucosal thickness, and presence of intestinal metaplasia. Statistical analyses demonstrated a significant positive correlation among all factors examined. The overall positivity rate of H. pylori in LSG specimens was 18.2% but ranged from 6.9-23.8% depending on whether the treating clinician performed routine pre-surgical endoscopy. The presence of H. pylori was associated with a higher average chronic inflammation grade, intestinal metaplasia, thicker mucosa, and presence of lymphoid follicles with germinal centers in the mucosa.

Histopathological Findings in Turkish Patients Undergoing Sleeve Gastrectomy: Is Histopathologic Examination of Sleeve Gastrectomy Specimens Clinically Important?

PURPOSE

Sleeve gastrectomy (SG) is a widely used surgical method in the treatment of obesity. This study aimed to reveal the histopathological changes in SG materials and to investigate the prevalence of clinically important lesions requiring follow-up.

MATERIALS AND METHODS

Three hundred five patients' data who underwent SG were analyzed. Cases were divided into three groups as normal, chronic inactive gastritis (CIG), and chronic active gastritis (CAG). Age, gender, and body mass index (BMI) of the three groups and the differences in the gastritis parameters of CIG and CAG groups were compared.

RESULTS

Thirty-three patients (10.8%) were in the normal group, 145 (47.5%) were in the CIG group, and 127 (41.6%) were in the CAG group. Preoperative endoscopic examination was performed in all cases, but Helicobacter pylori (HP) treatment was not applied. HP were detected in 39.3%, atrophy in 3.9%, intestinal metaplasia (IM) in 4.9%, and lymphoid follicle (LF) in 30% of the cases. Inflammation, atrophy, IM, LF, and HP were significantly higher in the CAG group. The proton pump inhibitor (PPI)-related changes were seen in 20 cases and it was more frequent in the CIG group. Intramucosal signet ring cell carcinoma was detected in 1 case. Endocrine cell hyperplasia and dysplasia were present in 7 cases with CAG. Multiple grade 1 neuroendocrine tumors were detected in just 1 case.

CONCLUSION

In our SG specimens, HP and clinically important lesions were significantly higher in the CAG group. Pathological examination should be carefully done as the lesions detected in SG specimens can change patient management.

Association of Hypercholesterolemia With Gastric Intestinal Metaplasia, Findings After Sleeve Gastrectomy Pathology Review

BACKGROUND

We evaluated the relationship between comorbidities associated with obesity, body mass index (BMI), and development of intestinal metaplasia (IM) after vertical sleeve gastrectomy (VSG).

MATERIALS AND METHODS

All VSG specimens performed at an academic center between 2011 and 2018 were reviewed. All specimens underwent histopathologic assessment, while those with findings suspicious for IM underwent additional immunohistochemical work up. Baseline patient characteristics and demographic data were obtained from Iran National Obesity Surgery Database by retrospective review.

RESULTS

A total of 862 adult individuals underwent VSG during the study period and specimens were histopathologically examined. All patients had preoperative upper endoscopy. The most common histopathologic diagnosis was miscellaneous findings (57.8%) followed by no pathologic finding (36.7%). The minority of patients (5.5%) had IM. Although 40.5% of patients had positive Helicobacter pylori infection preoperatively, just 13.8% had still positive infection postoperatively. A significant association was found between IM and hypercholesterolemia (odds ratio: 1.95; 95% confidence interval: 1.1, 3.5).

CONCLUSION

This study found a correlation between histopathologic changes in patients with IM and hypercholesterolemia. Prospective research studies are recommended to further examine this correlation.

Preoperative Assessment of Patients Undergoing Bariatric Sleeve Gastrectomy: A Cross-Sectional Study

Introduction

Saudi Arabia (SA) is one of the top countries in the world when it comes to the number of bariatric procedures performed each year. There is still some debate on whether to do regular or selective upper endoscopy during the preoperative examination. The purpose of this study was to explore various endoscopic findings and Helicobacter pylori (HP) infection in symptomatic and asymptomatic patients having laparoscopic sleeve gastrectomy (LSG) prior to surgery.

Methods

We investigated a cohort of 132 patients referred to the endoscopy unit from the bariatric surgery outpatient clinic for prebariatric esophagogastroduodenoscopy (EGD) as a part of preoperative LSG. Data extraction from medical records included clinical data such as body mass index (BMI), gastrointestinal symptoms (that include heartburn, regurgitation, epigastric pain, and nausea), medical comorbidities, and laboratory investigations. It included data about the endoscopic findings of EGD procedure as esophageal, gastric, and duodenal findings results as well as the results of biopsy specimens that were taken.

Results

Out of 132 patients, 29 (22%) had a BMI of less than 40 kg/m2 whereas 103 (78%) had a BMI of 40 kg/m2 or above, with an average of 44.4 ± 6.4 kg/m2. The average age of participants was 33.6 ± 10.4 years. HP was detected in 36 patients (35.0%) with a slightly greater prevalence in patients with a higher BMI (33.7%) than in patients with lower BMI (35.0%). Collectively, 73 patients (55.7%) had positive endoscopic findings of various grades, sites, and combinations. Incompetent cardia (35.6%) was the most often seen esophageal finding, antral gastritis (34.1%) was the most frequently encountered gastric finding, and duodenitis 1st part was the commonest duodenal endoscopic finding (7.8%). Among asymptomatic patients, incompetent cardia was detected in 33.3%, antral gastritis was found in 30.1%, and around one-quarter of them were positive on HP testing (26.6%). Additionally, 16.1% of them had signs of reflux esophagitis, 17.2% had hiatal hernia, and 14.0% had nodular gastritis.

Conclusion

The current study revealed a high prevalence of positive endoscopic findings as well as HP infection upon routine endoscopic examination among patients undergoing bariatric surgery even those who were asymptomatic from any gastrointestinal symptoms.

Helicobacter pylori-Related Metabolic Parameters and Premalignant Gastric Mucosa Histological Lesions in Swiss Bariatric Patients

Obesity, as a major risk factor of metabolic syndrome (MetS), represents a pandemic, especially in Western societies, and is considered a risk factor for malignancies. Helicobacter pylori (Hp), is a definite carcinogen with global distribution. We aimed to investigate, for the first time in Switzerland, the main gastric mucosa premalignant histological lesions of bariatric patients in correlation with MetS components and Hp Infection (Hp-I). By reviewing retrospectively 94304 patient cases, a total of 116 eligible patients having undergone bariatric surgery were identified. The mean patient age was 48.66 years. Hp(+) patients were 24% (28/116). Presence of gastric mucosa atrophy was documented in 8/28 Hp(+) patients (29%) and (2/88) Hp(-) ones (2%) (p = 0.006). Gastric mucosa intestinal metaplasia was observed in 14/28 (50%) Hp(+) patients versus 3/88 (3.4%) of Hp(-) group (p < 0.0001). Hp(+) patients exhibited statistically higher arterial hypertension (p = 0.033). The homeostatic model of assessment insulin resistance was also statistically significantly higher for the Hp(+) group (p < 0.001). In a multivariate analysis, including arterial hypertension, gastric mucosa atrophy, and intestinal metaplasia as variables, statistical significance remained only for intestinal metaplasia (p = 0.001). In conclusion, Hp-I is associated with premalignant gastric mucosa histologic lesions and MetS components, including arterial hypertension and IR. Further large-scale prospective studies are required to confirm these findings.

Histologic and Cost-Benefit Analysis of Laparoscopic Sleeve Gastrectomy Specimens Performed for Morbid Obesity

CONTEXT.—

Laparoscopic sleeve gastrectomy (LSG) has quickly become the bariatric surgical procedure of choice for patients with obesity who have failed medical management. Laparoscopic sleeve gastrectomy results in a gastric remnant that is routinely subject to pathologic examination.

OBJECTIVE.—

To perform a histologic and cost-benefit analysis of gastric remnants post-LSG.

DESIGN.—

All LSG cases performed at University Health Network, Toronto, Ontario, Canada, between 2010 and 2019 were reviewed. Specimens that underwent routine histopathologic assessment and ancillary immunohistochemical analysis were analyzed. Baseline patient characteristics and surgical outcomes were obtained from our internal database. The total cost of specimen gross preparation, examination, sampling, and producing and reporting a hematoxylin-eosin slide was calculated.

RESULTS.—

A total of 572 patients underwent LSG during the study period and had their specimens examined histologically. A mean of 4.87 blocks generating 4 hematoxylin-eosin slides was produced. The most common histologic findings reported in LSG specimens ranged from no pathologic abnormalities identified together with proton pump inhibitor-related change. A minority of cases demonstrated clinically actionable histologic findings, of which Helicobacter pylori infection was the most common. The total cost for the complete pathologic analysis of these cases amounted to CaD $66 383.10 (US $47 080.21) with a mean of CaD $116.05 (US $82.40) per case. A total of CaD $62 622.75 (US $44 413.30) was spent on full examination of cases that had no further postoperative clinical impact.

CONCLUSIONS.—

There is a broad spectrum of pathologic findings in LSG specimens, ranging from clinically nonactionable to more clinically actionable. The vast majority of histologic findings had no clinical impact, with only a minority of cases being clinically significant. This study therefore recommends that LSG specimens be subject to gross pathologic examination in the vast majority of cases. However, sections should be submitted for microscopic analysis if grossly evident lesions are present and if there is a clinical/known history of clinically actionable findings.

Inflammatory Cell Numbers in the Stomach of Japanese Subjects with Endoscopically Normal Mucosa without Helicobacter pylori Infection

INTRODUCTION

Since inflammatory cells, such as lymphocytes and plasma cells, normally inhabit the stomach, the border between normal and mild inflammation is difficult to visually determine using the updated Sydney system scale of gastritis. Additionally, eosinophils in the gastric mucosa must be counted to diagnose eosinophilic gastritis. We aimed to determine the normal number of inflammatory cells in patients with endoscopically normal mucosa and without Helicobacter pylori infections.

METHODS

We assessed patients aged 20-79 years, who had undergone upper gastrointestinal endoscopy at Kawasaki Medical School Hospital between January 2010 and December 2014. Inflammatory cells were counted in 1,000 μm2 fields of pyloric and fundic gland mucosal biopsy specimens. We finally included 325 (male, n = 141; female, n = 184; average age = 49.3 years) patients without inflammation who had H. pylori-negative endoscopic results and negative histological findings interpreted based on the updated Sydney System and the Kyoto classification of gastritis.

RESULTS

The average numbers of nucleated cells were 83.3 ± 14.2 and 65.4 ± 12.6/mm2 in the pyloric and fundic gland mucosae, respectively. Inflammatory cells were significantly more abundant in the pyloric mucosa than in the fundic gland mucosa (p < 0.05). Age and sex distribution did not significantly differ. Eosinophils were absent or scanty in the gastric mucosae of both glands in all patients.

CONCLUSION

We determined the absolute values of inflammatory cells, including eosinophils, in normal mucosae of pyloric and fundic glands. These findings could be important in defining gastric mucosal inflammation, including eosinophilic gastritis diagnosis.

Helicobacter pylori Prevalence in Laparoscopic Sleeve Gastrectomy Specimen

Introduction

Laparoscopic sleeve gastrectomy (LSG) has become a common surgical procedure. The value of routine histopathologic examination of the LSG specimens remains, however, a controversial issue. Helicobacter pylori was the most prevalent finding in several previous studies, but the overall results were dissimilar. We aim to assess the prevalence of Helicobacter pylori and other histopathologic findings in LSG specimens and the effect of increasing the number of sections for histology, from LSG specimens, on the rates of abnormal findings.

Methods

We retrospectively reviewed the histopathologic data of all patients who had undergone LSG, in a tertiary care center, over a 4-year period (n = 481). Patient characteristics and histopathologic findings were recorded and analyzed.

Results

Inactive chronic gastritis was the most common histopathologic finding (62.16%) followed by Helicobacter pylori gastritis (35.34%). Intestinal metaplasia was identified in 1.66% of the cases. There was no diagnosis of malignancy. Increasing the number of sections submitted for histopathologic examination resulted in a significantly higher rate of H. pylori gastritis detection.

Conclusion

Routine histopathologic examination of LSG specimens may detect H. pylori in a significant proportion of patients, and increasing the number of sections for histology from LSG specimens improves the rate of detection of this bacterium and identifies individuals who may benefit from treatment.

Review of pathological findings in laparoscopic sleeve gastrectomy specimens performed for morbid obesity

BACKGROUND

Bariatric surgical procedures are employed when there is a failure of lifestyle modification in arresting obesity. Laparoscopic sleeve gastrectomy (LSG) is quickly becoming the bariatric surgical procedure of choice. LSG results in a gastric remnant that is subject to pathological examination. The objective of this paper is to review the literature in regard to histological findings identified in gastric remnants post-LSG and identify the most pertinent histological findings.

MATERIALS AND METHODS

A literature search was performed to identify relevant case series. Data gathered from relevant case series then underwent statistical analysis.

RESULTS

The most common histological findings in an LSG specimen were clinically indolent findings such as no pathological abnormalities identified followed by non-specific gastritis. A minority of cases demonstrated clinically actionable findings for which Helicobacter pylori represented the majority of these findings.

CONCLUSION

There is a broad spectrum of pathological findings in LSG specimens, ranging from clinically indolent to clinically actionable. The most common histological findings are clinically indolent and only a small portion are of clinical significance and, hence, actionable.