Can Incidental Gastric GISTs During Bariatric Surgeries Change the Primary Plan of Surgery? A Single Team Experience and a Systematic Review of Literature

As bariatric surgeries (BS) increase, more incidental findings are liable to be discovered. Incidental gastric gastrointestinal stromal tumors (GISTs) during BS can be found in around 0.7% of the cases. In this article, we have performed a systematic review of the literature and added our data to those of the review to review a conceptual treatment strategy to both improve patient outcomes and decrease the risk of overall cancer. With the rise of new bariatric techniques, we have proposed a new classification to BS to enhance our description of the treatment strategy.

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.

Rare serosal cystic gastric gastrointestinal stromal tumor with extensive intestinal metaplasia in an adherent gastric mucosa; a case report in a 65-year-old male

Gastrointestinal (GI) intestinal stromal tumors account for 60% of mesenchymal GI tract tumors commonly located in the stomach and small intestine, predominantly solid tumors that rarely undergo cystic degeneration. A 65-year-old patient with increasing upper abdominal swelling and a computed tomography scan abdomen showed a large unilocular 17 × 16 × 15 cm lesion. A colossal cystic swelling in the lesser omentum, anterior to the stomach, was found upon exploration. Histopathological examination showed a spindle cell tumor turned out to be CD117 positive and S100 negative on immunostains. The tumor was moderate risk gastric gastrointestinal intestinal stromal tumor (GIST) based on the site; Stomach, Size >10 cm; Mitosis <5/5 mm² according to risk assessment of GIST, 2006. GISTs are predominantly solid tumors and rarely undergo cystic transformation. The primary differential diagnoses of spindle cell neoplasm are GISTs, Leiomyoma, Leiomyosarcoma and Schwannoma. These spindle cell neoplasms are differentiated by applying a panel of Immunohistochemical stains, CD117, SMA and S100.

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.

Trends in bariatric surgery and incidentalomas at a single institution in Saudi Arabia: a retrospective study and literature review

BACKGROUND

Data are lacking on trends in bariatric surgery and the frequency of incidental findings in Saudi Arabia.

OBJECTIVE

Report on trends in bariatric surgery as well as our experience in incidental findings along with a literature review (mainly on gastrointestinal stromal tumor).

DESIGN

Retrospective chart and literature review.

SETTINGS

Academic tertiary care center.

PATIENTS AND METHODS

We conducted a retrospective study at King Khalid University Hospital and analyzed the data collected from 2009 to 2019. We collected data on age, body mass index (BMI), H pylori infection, type of bariatric surgery performed, and type and location of incidental findings.

MAIN OUTCOME MEASURES

Incidental findings during or after bariatric surgery (in pathology specimen).

SAMPLE SIZE

3052 bariatric surgeries, 46 patients with incidentalomas.

RESULTS

The mean and standard deviation for the age of the 46 patients with incidentalomas was 42.1 (13.9) years and the mean (SD) preoperative BMI was 43.4 (6.4) kg/m². Of 3052 bariatric surgeries performed, the most common type was sleeve gastrectomy (93.9%), followed by gastric bypass surgery (4.58%) and gastric banding (1.47%). The total frequency of incidentalomas was 1.5%; 10.8% of patients had gastrointestinal stromal tumors (GIST), with the stomach being the commonest site for incidental findings. Eighty percent of the patients with GIST were positive for H pylori (P=.01 vs negative patients).

CONCLUSION

The number of incidentalomas and other findings were consistent with other reports. All these findings suggest that bariatric surgeons should take special care before, during, and after a laparoscopic operation in obese patients.

LIMITATIONS

Since this is a single-center, retrospective study, we did not collect data on important variables such as gender, socioeconomic status of the patient, and family history of obesity, and we did not perform a preoperative esophagogastroduodenoscopy.

CONFLICT OF INTEREST

None.

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.

Pathologic findings of the removed stomach during sleeve gastrectomy

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is the preferred surgical intervention to treat morbid obesity. Despite the rising popularity of LSG, little is known on the histopathologic findings of the resected partial stomach specimens. Our study aims to identify prevalent pathologic findings of the removed stomach and explore the association between patient characteristics and abnormal findings.

METHODS

A retrospective analysis was conducted using a prospectively maintained database of 649 patients who underwent LSG between November 1, 2013 and December 31, 2015 at our institution. Patient characteristics included age, body mass index, gender, and preoperative comorbidities (diabetes, hyperlipidemia, depression, gastroesophageal reflux, hypertension, and sleep apnea). Statistical analysis was performed using descriptive analysis and logistic regression models.

RESULTS

Abnormal pathologic findings were identified in approximately one-fifth (n = 142, 21.9%) of the patients. The most common find is non-specific chronic gastritis (9.7%), followed by Helicobacter pylori gastritis (4.9%). Approximately 15% of patients had significant histopathological alterations that might require further investigation, treatment, or follow-up, including non-specific chronic gastritis, H. pylori gastritis, autoimmune atrophic gastritis, and gastrointestinal stromal tumor. The odds of abnormal findings in patients without hyperlipidemia was 0.09 times the corresponding odds in those with hyperlipidemia (95% CI 0.03-0.29), controlling for factors including age, body mass index, gender, and other preoperative comorbidities.

CONCLUSION

Patients with gastroesophageal reflux and hyperlipidemia might suggest higher incidence rate of gastric histopathologic abnormalities. Routine preoperative screening may not be beneficial for patients undergoing sleeve gastrectomy.

Long intergenic noncoding RNA 01296 aggravates gastric cancer cells progress through miR-122/MMP-9

Long non-coding RNAs (lncRNAs) play important roles on tumor development and progression in gastric cancer (GC). However, the biological function and regulatory mechanisms of LINC01296 in GC still remain unknown. The objective of this study is to investigate the clinical significance and pathological roles of LINC01296 in GC. Results showed that LINC01296 was up-regulated in GC tissue and correlated with poor prognosis. In vitro, LINC01296 knockdown was up-regulated in GC cells and LINC01296 knockdown suppressed GC cells proliferation, migration and invasion, and promoted apoptosis. In vivo xenograft assays, results showed LINC01296 knockdown significantly inhibited GC tumor growth. Bioinformatics analysis revealed that LINC01296 sponged miR-122, which was proved to target MMP-9. Western blot and RT-PCR showed that LINC01296 was positively correlated with MMP-9 expression, while miR-122 was negatively correlated to it. Overall, results indicate that LINC01296 acts as oncogenic lncRNA in GC carcinogenesis, suggesting the LINC01296/miR-122/MMP-9 regulatory pathway in GC tumorigenesis.