Comparison of Safety and Outcomes between Endoscopic and Surgical Resections of Small (≤ 5 cm) Primary Gastric Gastrointestinal Stromal Tumors

Efficacy of real-time artificial intelligence-aid endoscopic ultrasonography diagnostic system in discriminating gastrointestinal stromal tumors and leiomyomas: a multicenter diagnostic study

Background

Gastrointestinal stromal tumors (GISTs) represent the most prevalent type of subepithelial lesions (SELs) with malignant potential. Current imaging tools struggle to differentiate GISTs from leiomyomas. This study aimed to create and assess a real-time artificial intelligence (AI) system using endoscopic ultrasonography (EUS) images to differentiate between GISTs and leiomyomas.

Methods

The AI system underwent development and evaluation using EUS images from 5 endoscopic centers in China between January 2020 and August 2023. EUS images of 1101 participants with SELs were retrospectively collected for AI system development. A cohort of 241 participants with SELs was recruited for external AI system evaluation. Another cohort of 59 participants with SELs was prospectively enrolled to assess the real-time clinical application of the AI system. The AI system's performance was compared to that of endoscopists. This study is registered with Chictr.org.cn, Number ChiCT2000035787.

Findings

The AI system displayed an area under the curve (AUC) of 0.948 (95% CI: 0.921-0.969) for discriminating GISTs and leiomyomas. The AI system's accuracy (ACC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) reached 91.7% (95% CI 87.5%-94.6%), 90.3% (95% CI 83.4%-94.5%), 93.0% (95% CI 87.2%-96.3%), 91.9% (95% CI 85.3%-95.7%), and 91.5% (95% CI 85.5%-95.2%), respectively. Moreover, the AI system exhibited excellent performance in diagnosing ≤20 mm SELs (ACC 93.5%, 95% CI 0.900-0.969). In a prospective real-time clinical application trial, the AI system achieved an AUC of 0.865 (95% CI 0.764-0.966) and 0.864 (95% CI 0.762-0.966) for GISTs and leiomyomas diagnosis, respectively, markedly surpassing endoscopists [AUC 0.698 (95% CI 0.562-0.834) for GISTs and AUC 0.695 (95% CI 0.546-0.825) for leiomyomas].

Interpretation

We successfully developed a real-time AI-assisted EUS diagnostic system. The incorporation of the real-time AI system during EUS examinations can assist endoscopists in rapidly and accurately differentiating various types of SELs in clinical practice, facilitating improved diagnostic and therapeutic decision-making.

Funding

Science and Technology Commission Foundation of Shanghai Municipality, Science and Technology Commission Foundation of the Xuhui District, the Interdisciplinary Program of Shanghai Jiao Tong University and the Research Funds of Shanghai Sixth people's Hospital.

Gastric gastrointestinal stromal tumors: therapeutic strategies and long-term prognosis

OBJECTIVES

This study aimed to evaluate the clinical and prognostic characteristics of primary gastric gastrointestinal stromal tumors (GIST).

METHODS

Patients who underwent resection for primary gastric GIST between January 2002 and December 2017 were included. Recurrence-free survival (RFS) was calculated by Kaplan-Meier analysis, and Cox proportional hazards model was used to identify independent prognostic factors.

RESULTS

Altogether, 653 patients were enrolled. The median patient age was 59 years (range 15-86 years). Open, laparoscopic, and endoscopic resections were performed in 394 (60.3%), 105 (16.1%), and 154 (23.6%) patients, respectively. According to the modified NIH consensus classification, 132 (20.2%), 245 (37.5%), 166 (25.4%), and 88 (13.5%) patients were categorized into very low-, low-, intermediate-, and high-risk, respectively. A total of 136 (20.8%) patients received adjuvant imatinib treatment. The median follow-up time was 78 months (range 4-219 months), and the estimated 5-year RFS rate was 93.0%. In all patients, tumor size and rupture, mitotic counts, and adjuvant imatinib treatment were independent prognostic factors. The prognosis of gastric GIST treated with endoscopic resection was not significantly different from that of laparoscopic or open resection after adjusting for covariates using propensity score matching (log-rank p = .558). Adjuvant imatinib treatment (HR = 0.151, 95%CI 0.055-0.417, p < .001) was a favorable prognostic factor for high-risk patients, but was not associated with prognosis in intermediate-risk patients.

CONCLUSION

Patients with small gastric GISTs who successfully underwent endoscopic resection may have a favorable prognosis. Adjuvant imatinib treatment improve the prognosis of high-risk gastric GISTs, however, its use in intermediate-risk patients remains controversial.

Goldilocks principle of minimally invasive surgery for gastric subepithelial tumors

BACKGROUND

Minimally invasive surgery had been tailored to individual cases of gastric subepithelial tumors (SETs) after comparing the clinical outcomes of endoscopic resection (ER), laparoscopic resection (LR), and hybrid methods.

AIM

To study the use of Goldilocks principle to determine the best form of minimally invasive surgery for gastric SETs.

METHODS

In this retrospective study, 194 patients of gastric SETs with high probability of surgical intervention were included. All patients underwent tumor resection in the operating theater between January 2013 and December 2021. The patients were divided into two groups, ER or LR, according to the tumor characteristics and the initial intent of intervention. Few patients in the ER group required further backup laparoscopic surgery after an incomplete ER. The patients who had converted open surgery were excluded. A logistic regression model was used to assess the associations between patient characteristics and the likelihood of a treatment strategy. The area under the curve was used to assess the discriminative ability of tumor size and Youden's index to determine the optimal cut-off tumor size.

RESULTS

One-hundred ninety-four patients (100 in the ER group and 94 in the LR group) underwent tumor resection in the operating theater. In the ER group, 27 patients required backup laparoscopic surgery after an incomplete ER. The patients in the ER group had small tumor sizes and shorter procedure durations while the patients in the LR group had large tumor sizes, exophytic growth, malignancy, and tumors that were more often located in the middle or lower third of the stomach. Both groups had similar durations of hospital stays and a similar rate of major postoperative complications. The patients in the ER group who underwent backup surgery required longer procedures (56.4 min) and prolonged stays (2 d) compared to the patients in the LR group without the increased rate of major postoperative complications. The optimal cut-off point for the tumor size for laparoscopic surgery was 2.15 cm.

CONCLUSION

Multidisciplinary teamwork leads to the adoption of different strategies to yield efficient clinical outcomes according to the tumor characteristics.

Comparison of Modified Cap-Assisted Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection in Treating Intraluminal Gastric Gastrointestinal Stromal Tumor (≤20 mm)

INTRODUCTION

A modified cap-assisted endoscopic mucosal resection (mEMR-C), introduced in this study, was a novel variation of the standard EMR. We aimed to compare the outcomes of mEMR-C and endoscopic submucosal dissection (ESD) for the treatment of small (≤20 mm) intraluminal gastric gastrointestinal stromal tumors (gGISTs).

METHODS

This retrospective study included 43 patients who underwent mEMR-C and 156 patients who received ESD at Nanjing Drum Tower Hospital. Baseline characteristics, adverse events, and clinical outcomes were compared between the 2 groups. Univariate and multivariable analyses were conducted to adjust for confounders. After propensity score matching using sex, year, location, and tumor size, outcomes were compared with 41 patients in each group.

RESULTS

A total of 199 patients underwent endoscopic resection and the en bloc resection rate was 100%. The complete resection rate was comparable in both groups ( P = 1.000). Approximately 9.5% of all patients had a positive margin. There was no significant difference in positive margin for patients undergoing mEMR-C or ESD (9.3% vs 9.6%, P = 1.000). No difference in adverse events in both groups ( P = 0.724). The mEMR-C was associated with shorter operation time and lower cost than the ESD. Recurrence was reported in 2 patients at 1 and 5 years after ESD during a median follow-up of 62 months. No metastasis and disease-related death were identified in both groups. Propensity score matching analysis revealed similar results.

DISCUSSION

The mEMR-C was found to be the preferable technique for small (≤20 mm) intraluminal gGISTs with shorter operation time and lower cost as compared with ESD.

Prognostic analysis of 2-5 cm diameter gastric stromal tumors with exogenous or endogenous growth

BACKGROUND

There has been limited research on the prognosis differences in patients with gastric stromal tumor invasion of the plasma membrane surface. This study intended to investigate whether there is a difference in prognosis in patients with endogenous or exogenous 2-5 cm diameter GISTs.

METHODS

We retrospectively analyzed the clinicopathological and follow-up data of gastric stromal tumor patients, all of whom underwent surgical resection for primary GIST at Nanjing Drum Tower Hospital from December 2010 to February 2022. We classified patients based on tumor growth patterns and then investigated the association between tumor growth patterns and clinical outcomes. Progression-free survival (PFS) and overall survival (OS) were calculated by the Kaplan‒Meier method.

RESULTS

A total of 496 gastric stromal tumor patients were enrolled in this study, among which 276 patients had tumors of 2-5 cm in diameter. Of these 276 patients, 193 had exogenous tumors, and 83 had endogenous tumors. Tumor growth patterns were significantly related to age, rupture status, resection style, tumor site, tumor size, and intraoperative bleeding. According to Kaplan‒Meier curve analysis, the tumor growth pattern among patients with 2-5 cm diameter tumors was significantly correlated with worse progression-free survival (PFS). Ultimately, multivariate analyses identified the Ki-67 index (P = 0.008), surgical history (P = 0.031), and resection style (P = 0.045) as independent prognostic markers for PFS.

CONCLUSIONS

Although gastric stromal tumors with a diameter of 2-5 cm are classified as low risk, the prognosis is lower for exogenous tumors than for endogenous tumors, and exogenous gastric stromal tumors have a risk of recurrence. Consequently, clinicians should be vigilant regarding the prognosis of patients with this type of tumor.

Clinical Efficacy and Safety of Endoscopic Treatment of Gastrointestinal Stromal Tumors in the Stomach

Background/Aims

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors in the stomach. We evaluated the clinical outcomes of endoscopic treatment for gastric GISTs.

Methods

This is a single center, retrospective study that enrolled 135 cases of gastric subepithelial tumors (SETs) resected by endoscopic procedures and confirmed as GISTs by histopathology from March 2005 to July 2019. The immediate and long-term clinical outcomes were analyzed retrospectively.

Results

The mean patient age was 57.9 years, and the mean tumor size was 2.1 cm. Of the tumors, 43.0% were located in the body, followed by the fundus (26.7%) and cardia (17.0%). Most tumors (85.2%) were resected by endoscopic submucosal dissection, followed by endoscopic mucosal resection (6.7%), submucosal tunneling endoscopic resection (5.9%), and endoscopic full-thickness resection (2.2%). Macroperforation occurred in 4.4% and microperforation in 6.7% of the cases. The R0 resection rate was 15.6%. However, the rate of complete resection by the endoscopic view was 90.4%, of which 54.8% of cases were in the very-low-risk group, followed by the low-risk group (28.1%), intermediate-risk group (11.9%), and high-risk group (5.2%). During 36.5 months of follow-up, recurrence was found in four (3.4%) of the 118 patients who were monitored for more than 6 months (low-risk group, 1/37 [2.7%]; intermediate-risk group, 2/11 [18.2%]; high-risk group, 1/6 [16.7%]).

Conclusions

Endoscopic treatment of a GIST appears to be a feasible procedure in selected cases. However, additional surgery should be considered if the pathologic results correspond to intermediate- or high-risk groups.

Gastric defect closure after endoscopic full-thickness resection: the closing while dissecting technique

BACKGROUND

Complete closure of gastric wall defects is critical following endoscopic full-thickness resection (EFTR). The aim of this study was to evaluate the efficacy, safety, and clinical outcome of a new endoscopic method: closing while dissecting.

METHODS

Twenty-seven patients who underwent EFTR were retrospectively analyzed between January 2020 and March 2021. Gastric defects resulting from EFTR were closed using the "interrupted-close during dissection" technique with endoclips. Tumor characteristics, en bloc resection rates, and postoperative adverse events were evaluated.

RESULTS

All submucosal tumors were successfully resected and complete resection was histologically confirmed. The mean maximal tumor diameter was 1.3 cm (ranging from 0.8 to 3.0 cm). The majority of these tumors were gastrointestinal stromal tumors (n = 20), Leiomyoma (n = 3), schwannomas (n = 2), others included fibroma (n = 1) and neurogenic tumor (n = 1). There were no cases of hemorrhage, peritonitis, or delayed perforation. Four patients complained of slight abdominal pain, but no hyperpyrexia or serious elevated white blood cell count was detected in the first 24 h after treatment. All wounds were healed on follow-up endoscopy 3 months after the procedure. The mean follow-up duration was 8.5 months (ranging from 3 to 17) and no tumor recurrences were observed.

CONCLUSIONS

The feasibility and safety of this interrupted-close during dissection approach allows for clinical applications in EFTR of gastric submucosal tumors.

Laparoscopic resection is not superior to endoscopic resection for relative small gastric gastrointestinal stromal tumors: A propensity score-matched study

Background and Aim

Endoscopic resection (ER) and laparoscopic resection (LAP) have been recommended for the treatment of gastric gastrointestinal stromal tumors (GISTs) less than 2 cm. However, the therapeutic approach for gastric GISTs between 2 and 5 cm in diameter is still under debate. In this retrospective study, we aimed to evaluate the feasibility, efficacy, and safety of ER for gastric GISTs (2–5 cm) compared with LAP.

Methods

From January, 2011 to January, 2018, 197 patients with GISTs at our institution with tumor diameter between 2 and 5 cm were included in our study. Clinical baseline characteristics, histopathological results, and perioperative outcomes were collected and compared in all the patients. Propensity score matching (PSM) methods were used to balance baseline characteristics.

Results

There was no significant difference in age (p = 0.246), gender (p = 0.572), tumor location (p = 0.333), pathological risk classification (p = 0.543), Ki-67 index (p = 0.212), and follow-up time (p = 0.831) in the ER and LAP groups. However, significance difference was found in times to liquid diet intake (4.45 ± 1.2 vs. 5.40 ± 1.5 days, p = 0.013) and hospital stays (7.72 ± 1.1 vs. 10.01 ± 1.3 days, p &lt; 0.001). During the follow-up period, there was one recurrence in the ER group vs. two recurrences in the LAP group. After PSM, the tumor size was balanced between the two groups with 49 patients in each group. The times to liquid diet intake (4.18 ± 1.3 vs. 5.16 ± 1.6 days, p = 0.042) and hospital stay days (7.12 ± 1.1 vs. 9.94 ± 1.3, p &lt; 0.0001) were still short in the ER group.

Conclusions

ER is more associated with a quick postoperative recovery than LAP. ER could be an alternative approach for gastric GISTs (2–5 cm). However, the long-term follow-up outcomes are still unclear and random control trials are needed.

Advances in endoscopic resection techniques of small gastric tumors originating from the muscularis propria

Gastrointestinal stromal tumors are common gastrointestinal tumors typically originating from the muscularis propria layer of the stomach. Small gastric stromal tumors are usually detected incidentally during routine endoscopic examination. Although they may have malignant potentially, controversies remain regarding the need for endoscopic resection of small gastric stromal tumors originating from the muscularis propria. According to the guidelines of the European Society of Medical Oncology, all gastrointestinal stromal tumors >2 cm in size should be resected with endoscopic surveillance recommended for tumors <2 cm. Endoscopic resection including endoscopic mucosal dissection (EMD), endoscopic submucosal dissection (ESD), submucosal tunneling endoscopic resection and snare assisted endoscopic resection. However, EMD and ESD procedures may be accompanied with serious complications including perforation, bleeding, and abdominal infection. Snare-assisted endoscopic resection is an alternative approach and has the advantages of a shorter procedure time and a low rate of perforation or bleeding. This study summarizes the safety and feasibility of a novel snare-assisted endoscopic resection technique and highlights the pros and cons of the different endoscopic approaches currently used for subepithelia small gastric tumors.

Effect of endoscopic resection of gastrointestinal stromal tumors in the stomach under double-channel gastroscopy: A retrospective observational study

We aimed to investigate the safety and efficacy of endoscopic resection for the treatment of gastric gastrointestinal stromal tumors (GISTs) under single-channel gastroscopy and double-channel gastroscopy. We identified 154 patients with GISTs of the stomach who underwent endoscopic resection and were retrospectively analyzed at our hospital between May 2016 and March 2020, including 49 patients by single-channel gastroscopy and 105 patients by double-channel gastroscopy. We observed the clinical efficacy, complications, and safety of endoscopic resection of gastric GISTs, and the data were evaluated retrospectively. All patients underwent endoscopic resection successfully, without conversion to open surgery. In the single-channel gastroscopy group, 7 patients had lesions in the gastric cardia, 17 in the gastric fundus, 20 in the gastric corpus, and 5 in the gastric antrum. In the double-channel gastroscopy group, 13 patients had lesions in the gastric cardia, 34 in the gastric fundus, 46 in the gastric body, 10 in the gastric antrum, 1 in the pylorus, and 1 in the gastric angular incisure. The double-channel gastroscopy group had a shorter operation time than the single-channel gastroscopy group (59.9 ± 34.9 minutes vs 74.8 ± 26.7 minutes; P = .009 and P < .01, respectively), while they also had a lower perforation rate than the single-channel gastroscopy group (34.3% vs 51.0%; P = .048 and P < .05, respectively). No residual or recurrent lesions were discovered in any patients by gastroscopy reexamination. Both single-channel gastroscopy and double-channel gastroscopy can provide safe, effective, feasible endoscopic resection. However, double-channel gastroscopy has some distinct advantages in endoscopic resection.

Comparison of safety and short-term outcomes between endoscopic and laparoscopic resections of gastric gastrointestinal stromal tumors with a diameter of 2-5 cm

BACKGROUND AND AIM

Developments of endoscopic techniques brought the possibility of endoscopic resection for gastrointestinal stromal tumors (GISTs) of larger sizes. We aim to compare safety and short-term outcomes between endoscopic and laparoscopic resections of gastric GISTs with a diameter of 2-5 cm.

METHODS

This is a single-center, retrospective cohort study. The clinical data, perioperative conditions, and the adverse events of patients who underwent endoscopic or laparoscopic resection for gastric GIST of 2-5 cm in Zhongshan Hospital, Fudan University, from January 2016 to December 2020 were retrospectively reviewed.

RESULTS

A total of 346 patients were reviewed; 12 patients who failed to accomplish the planned procedure were excluded; 182 underwent laparoscopic resection; and 152 underwent endoscopic resection. Significant differences exist in the tumor size between the laparoscopic group (3.43 ± 0.86 cm) and the endoscopic group (2.78 ± 0.73 cm) (P < 0.01). Compared with laparoscopic resection, endoscopic resection was associated with faster recovery (P < 0.01), shorter hospital stays (P < 0.01), and lower cost (P < 0.01). The incidence of Clavien-Dindo grade II-V adverse events in the endoscopic group (3/152) was significantly lower than that in the laparoscopic group (12/182) (P = 0.04). After a propensity score matching analysis, the endoscopic group showed similar incidences of complications with the laparoscopic group, while the advantages over laparoscopic resection in postoperative hospital stay, time to first oral intake, and hospitalization expenses remained significant (P < 0.01).

CONCLUSIONS

Endoscopic resection is a safe and cost-effective method for 2-5 cm of gastric GISTs compared with laparoscopic resection.

Comparison of effectiveness and safety between endoscopic and surgical resection for 2-5 cm gastric stromal tumors

BACKGROUND

As endoscopic resection remains controversial, this study aims to compare the effectiveness and safety between endoscopic and surgical resection for 2-5 cm gastric stromal tumors (GSTs).

METHODS

Patients with 2-5 cm GST resected at West China Hospital from March 2008 to April 2019 were enrolled. Propensity score matching (PSM) (1:1) was performed to achieve baseline data consistency.

RESULTS

112 patients were matched between the endoscopic resection group (ER) and the open surgery group. There were no significant differences in the complete resection rate (94.6% vs. 100%), the incidence of complications (25.0% vs. 14.3%), the recurrence rate (0% vs. 1.8%) and the 5-year relapse-free survival (100% vs. 97.9%) (P > 0.05). The ER had a shorter fasting time (3.5 days vs. 5 days), a shorter postoperative hospital stay (7 days vs. 8 days) and a lower hospitalization cost (3,589.16 USD vs. 5,931.24 USD) (P < 0.05). 54 cases were matched between the ER and the laparoscopic surgery group (LS). There were no significant differences in the complete resection rate (92.6% vs. 96.3%), the incidence of complications (22.2% vs. 11.1%), the fasting time (4 days vs. 3 days), the recurrence rate (0% vs. 3.7%) and the 5-year relapse-free survival (100% vs. 96.3%) (P > 0.05). The hospitalization cost (3,589.25 USD vs. 4,715.16 USD) was lower in the ER, and the postoperative hospital stay was shorter in the LS (6 days vs. 7 days) (P < 0.05).

CONCLUSIONS

Although slightly higher incidences of incomplete resection and perforation were shown in the endoscopic resection group, there was insignificant difference between groups (P > 0.05). Endoscopic resection might be an alternative surgical method for 2-5 cm GSTs.

Efficacy and Safety of Endoscopic Resection for Small Gastric Gastrointestinal Stromal Tumors in Elderly Patients

Background

Gastrointestinal stromal tumors (GISTs) are prevalent in elderly patients. Endoscopic resection has become popular for treating small (≤5 cm) gastric GISTs. However, little is known about the outcomes of endoscopic resection in elderly patients.

Aim

To assess the efficacy and safety of endoscopic resection for small (≤5 cm) gastric GISTs in elderly patients (≥65 years old).

Methods

A total of 260 patients (265 lesions) with gastric GISTs treated via endoscopic resection from January 2011 to May 2020 were retrospectively analyzed. Among them, 65 patients were ≥65 years old (elderly group), and 195 patients were <65 years old (nonelderly group). Clinicopathological characteristics, postoperative complications, and tumor recurrence rates between the two age groups were compared.

Results

A total of 260 patients with primary small (≤5 cm) gastric GISTs were treated with endoscopic resection. The median ages of the elderly and nonelderly groups were 68 (range 65-83) years and 55 (range 32-64) years, respectively. Elderly patients showed a higher incidence of comorbidities compared with nonelderly patients (61.5% versus 32.3%s, respectively; p < 0.001). All elderly patients and 99.0% of nonelderly patients underwent en bloc resection; only two nonelderly patients received piecemeal resection. No significant differences were found regarding postoperative complications or tumor recurrence rates between the two groups.

Conclusions

Although elderly patients had more comorbidities than nonelderly patients, both groups had similar postoperative complications and recurrence rates. We suggest that endoscopic resection performed by experienced endoscopists is safe and effective for treating small (≤5 cm) gastric GISTs in elderly patients.

The necessarity of treatment for small gastric subepithelial tumors (1-2 cm) originating from muscularis propria: an analysis of 972 tumors

Background and objectives

Up till now, there are still controversies about the specific indication of endoscopic resection for small gastric subepithelial tumors (gSETs) originating from muscularis propria. We aimed to investigate the safety of endoscopic resection and postoperative pathology analysis.

Method

The patients with primary small gSETs originating from muscularis propria, treated by endoscopic resection in the endoscopic center of Shengjing Hospital between January, 2011 and September, 2019 were enrolled. The complete resection rate, adverse events and clinicopathological features were recorded.

Result

A total of 936 patients with 972 gastric SETs ≤ 2 cm originating from muscularis propria were included in our study. All the lesions were successfully treated by endoscopic resection. Nearly half of lesions were proved to be gastrointestinal stromal tumor (GIST) [n = 411 (42.3%)] according to postoperative pathology. All the objects were further subdivided into 2 groups, ≤ 1 cm, > 1 and ≤ 2 cm gSETs. The risk of gastric GIST of intermediate/high risk in the group (> 1 and ≤ 2 cm gSETs) is 8.41 times as that of gastric GIST in the group (the size of gastric ≤ 1 cm gSETs) (P < 0.05).

Conclusion

Endoscopic resection is a safe and effective treatment for small gSETs. gSETs (1–2 cm) is more risky than gSETs (≤ 1 cm) and should be resected. This should be evaluated by further studies.

Predictors of the difficulty for endoscopic resection of gastric gastrointestinal stromal tumor and follow-up data

BACKGROUND AND AIM

Gastrointestinal stromal tumors (GISTs) are among the most common submucosal tumors in the stomach that require therapeutic intervention. We aim to identify the predictors of technical difficulty during endoscopic resection of gastric GIST and to investigate follow-up outcomes.

METHODS

Patients with gastric GISTs were reviewed from June 2009 to June 2020 at Zhongshan Hospital. Clinical and pathological features, endoscopic procedure information, and follow-up data were collected and analyzed. A nomogram was developed and validated internally and externally.

RESULTS

A total of 628 GISTs were finally analyzed. The difficulty was experienced in 66 cases. GISTs size (2-3 cm: OR 2.431 P = 0.018 and > 3 cm: OR 9.765 P < 0.001), invasion depth beyond submucosal (MP: OR 2.280, P = 0.038 and MP-ex: OR 4.295, P = 0.002), and lack of experience (OR 2.075, P = 0.016) were independent risk factors of difficulty. The nomogram prediction model showed a bias-corrected C-index value of 0.778 and acquired an area under curve (AUC) of 0.756 on the external validation cohort. At the cut-off of 0.15, the nomogram's negative predictive value (NPV) and accuracy (ACC) were 94.9% and 79.8% in identifying non-difficult GISTs. Follow-up results showed that only five GIST patients had local recurrence after endoscopic resection.

CONCLUSIONS

Tumor size, invasion depth, and endoscopists' experience were risk factors for the difficulty of endoscopic GIST resection. Our nomogram provided a valuable tool for screening non-difficult GIST resection.

Endoscopic Resection for Gastric Subepithelial Tumor with Backup Laparoscopic Surgery: Description of a Single-Center Experience

The aim of this study was to analyze patients who underwent endoscopic resection (ER) for gastric subepithelial tumors (SETs) with a high probability of surgical intervention. Between January 2013 and January 2021, 83 patients underwent ER at the operation theater and 27 patients (32.5%) required backup surgery mainly due to incidental perforation or uncontrolled bleeding despite endoscopic repairing. The tumor was predominantly located in the upper-third stomach (81%) with a size ≤ 2 cm (69.9%) and deep to the muscularis propria (MP) layer (92.8%) but there were no significant differences between two groups except tumor exophytic growth as a risk factor in the surgery group (37% vs. 0%, p < 0.0001). Patients in the ER-only group had shorter durations of procedure times (60 min vs. 185 min, p < 0.0001) and lengths of stay (5 days vs. 7 days, p < 0.0001) but with a higher percentage of overall morbidity graded III (0% vs. 7.1%, p = 0.1571). After ER, five patients (6%) had delayed perforation and two (2.4%) required emergent laparoscopic surgery. Neither recurrence nor gastric stenosis was reported during long-term surveillance. Here, we provide a minimally invasive strategy of endoscopic resection with backup laparoscopic surgery for gastric SETs.

Endoscopic Resection of Gastrointestinal Stromal Tumor: Is It Safe?

Recently, results from clinical studies of endoscopic resection of gastrointestinal stromal tumor (GIST) in the stomach are being reported. This procedure has several advantages, such as the provision of a definite diagnosis and therapeutic plan, avoidance of frequent follow-up examination, and reduction of patients’ anxiety. However, several concerns also exist such as a limited number of studies, low R0 resection rate, and relatively shorter follow-up period compared with surgical resection. Nevertheless, it is encouraging that most of the post-procedural complications have been treated with conservative management and that some of the patients did not show recurrence of the tumor during long-term follow-up. The selection of suitable cases and the experience of the endoscopists are the most important factors for successful endoscopic resection of gastric GIST. Development of novel procedures as well as collaboration with laparoscopic surgeons are currently in progress.

On the Track of New Endoscopic Alternatives for the Treatment of Selected Gastric GISTs-A Pilot Study

Background and Objectives: GISTs (Gastrointestinal stromal tumors) are the most common mesenchymal gastrointestinal tract tumours and are mainly located in the stomach. Their malignant potential depends on size, location, and type. Endoscopic techniques are a less invasive modality for patients not eligible for surgery. ESD (endoscopic submucosal dissection) is mainly used for the removal of smaller GISTs, with intraluminal growth and a more superficial location. Thus, R0 resection capability in some cases may be not sufficient, limited by tumour size, location in the gastric wall, and its connection level with the muscularis propria. In such cases, an endoscopic full-thickness resection can become a new alternative. In this retrospective pilot study, we evaluated ESD and hybrid resection techniques in terms of safety, efficacy, and disease recurrence for selected types of gastric GISTs. Materials and Methods: A retrospective comparison was conducted in a group of patients who underwent ESD or a hybrid technique combining endoscopic resection with endoscopic suturing using the OverStitch system (HT) for type II or III gastric GISTs. A total of 21 patients aged 70 ± 8 years underwent endoscopic resection. Seventeen lesions were treated with ESD and four with the HT. Results: R0 resection was achieved in all patients treated using HT (type III lesions) and in 53% of those treated with ESD (p = 0.08). None of the type III lesions treated with ESD were excised with R0. Lesions treated with R0 ESD resections were significantly smaller (1.76 ± 0.35 cm) than those with R1 ESD resections (2.39 ± 0.40 cm) (p < 0.01). The mean lesion size treated with the HT was 2.88 ± 0.85 cm. Conclusions: HT may be a new resection modality for large gastric GISTs with high muscularis propria connection grades. Further studies are required to evaluate its safety and efficacy and to form precise inclusion criteria for endoscopic resection techniques.

Endoscopic obturation with tissue adhesive for bleeding gastric stromal tumor: a case report

Primary endoscopic hemostasis for bleeding gastrointestinal stromal tumor (GIST) is rarely reported. Herein, we report the case of a patient with a bleeding GIST that was treated with endoscopic obturation with tissue adhesive. A 46-year-old man presented with hematemesis and tarry stool for 1 day. Upper GI endoscopy revealed a bleeding submucosal tumor at the stomach fundus and an exposed pulsatile vessel was seen at the defect. Endoscopic obturation with tissue adhesive was performed to treat the defect and the bleeding was successfully stopped. No recurrence of bleeding was observed through a gastric tube, and 6 days after endoscopic obturation, the patient underwent laparoscopic partial gastrectomy. Endoscopic obturation with tissue adhesive is a feasible and effective method to treat bleeding GIST.

Controversies in EUS: Do we need miniprobes?

This is the fifth in a series of papers entitled "Controversies in EUS." In the current paper, we deal with high-resolution catheter probes, otherwise known as EUS miniprobes (EUS-MPs). The application of miniprobes for early carcinomas in the entire intestinal tract, for subepithelial lesions, and for findings in the bile duct and pancreatic duct as well as endobronchial use is critically discussed. Submucous lesions, especially in the colon, but also early carcinomas in special cases are considered the most important indications. The argument is illustrated by numerous examples.

Comparison of malignancy-prediction efficiency between contrast and non-contract CT-based radiomics features in gastrointestinal stromal tumors: A multicenter study

This work seeks the development and validation of radiomics signatures from nonenhanced computed tomography (CT, NE-RS) to preoperatively predict the malignancy degree of gastrointestinal stromal tumors (GISTs) and the comparison of these signatures with those from contrast-enhanced CT. A dataset for 370 GIST patients was collected from four centers. This dataset was divided into cohorts for training, as well as internal and external validation. The minimum-redundancy maximum-relevance algorithm and the least absolute shrinkage and selection operator (LASSO) algorithm were used to filter unstable features. (a) NE-RS and radiomics signature from contrast-enhanced CT (CE-RS) were built and compared for the prediction of malignancy potential of GIST based on the area under the receiver operating characteristic curve (AUC). (b) The radiomics model was also developed with both the tumor size and NE-RS. The AUC values were comparable between NE-RS and CE-RS in the training (.965 vs .936; P = .251), internal validation (.967 vs .960; P = .801), and external validation (.941 vs .899; P = .173) cohorts in diagnosis of high malignancy potential of GISTs. We next focused on the NE-RS. With 0.185 selected as the cutoff of NE-RS for diagnosis of the malignancy potential of GISTs, accuracy, sensitivity, and specificity for diagnosis high-malignancy potential GIST was 90.0%, 88.2%, and 92.3%, respectively, in the training cohort. For the internal validation set, the corresponding metrics are 89.1%, 94.9%, and 80.0%, respectively. The corresponding metrics for the external cohort are 84.6%, 76.1%, and 91.0%, respectively. Compared with only NE-RS, the radiomics model increased the sensitivity in the diagnosis of GIST with high-malignancy potential by 5.9% (P = .025), 2.5% (P = .317), 10.5% (P = .008) for the training set, internal validation set, and external validation set, respectively. The NE-RS had comparable prediction efficiency in the diagnosis of high-risk GISTs to CE-RS. The NE-RS and radiomics model both had excellent accuracy in predicting malignancy potential of GISTs.

Recent Anti-platelet Therapy Revealing Underlying Undiagnosed Gastrointestinal Stromal Tumor in Otherwise Healthy Patient

Gastrointestinal stromal tumors (GIST) are uncommon tumors of the gastrointestinal (GI) tract that arise from primitive mesenchymal cells. Usually, GIST presents as chronic gastrointestinal symptoms or obscure gastrointestinal bleed. Not many cases have been reported in the literature with acute symptoms in the setting of recent aspirin use. We report a case of 70-year-old male otherwise healthy who presented to the hospital with the complaint of black tarry stool for the past two days after taking one tablet of aspirin once a day for two days. The patient underwent upper endoscopy which showed a moderate size polypoid mass in the gastric fundus. Initially, standard endoscopic biopsy was negative for malignancy, due to high suspicion for GIST, later the patient underwent upper endoscopic ultrasound with fine-needle aspiration which confirmed low-grade GIST.