Endoscopic Evaluation and Management of Gastric Stromal Tumors

A rapid and simple endoscopic resection of gastric fundus submucosal tumors

A 56-year-old male patient was diagnosed with a submucosal tumor in the fundus of the stomach. The conventional operation method is endoscopic submucosal dissection. We present a case of rapid tumor resection without employing traditional endoscopic submucosal dissection instruments such as a mucotomy knife and endoscopic injection needle, resulting in substantial cost savings for the patients.

A nomogram prediction model for the risk of intra-abdominal infection after endoscopic full-thick resection of gastric submucosal tumors

Background

This study aimed to investigate the risk factors for complication of intra-abdominal infection (IAI) after endoscopic full-thickness resection of gastric submucosal tumors (GSMT) and to establish a nomogram prediction model for the occurrence of IAI.

Methods

Clinical data of patients with GSMT who underwent endoscopic full-thick resection (EFR) from January 2018 to July 2023 were retrospectively analyzed. The patients were divided into IAI and non-IAI groups according to whether IAI occurred during postoperative hospitalization. Univariate and multivariate logistic regression analyses were performed on the relevant clinical data of patients in the two groups to screen the independent influencing factors for the occurrence of IAI. The nomogram model was constructed based on the independent influencing factors. Model discrimination was assessed by the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. The consistency of model-predicted risk with actual risk was evaluated using the Hosmer-Lemeshow goodness-of-fit test. The clinical performance of the nomogram model was evaluated using decision curve analysis.

Results

A total of 240 GSMT patients who underwent EFR procedures were finally included in this study, including 14 patients (5.83 %) in the IAI group and 226 patients in the non-IAI group. Univariate and multivariate logistic regression analyses showed that age (OR = 1.283, 95 % CI = 1.029-1.600), preoperative albumin (OR = 0.575, 95 % CI = 0.395-0.837), duration of operation (OR = 1.222, 95 % CI = 1.060-1.409), and hospitalization time (OR = 4.089, 95 % CI = 1.190-14.043) were independent influencing factors for the incidence of IAI in GSMT patients undergoing EFR surgery (P < 0.05). A Nomogram model was established based on the above factors. The Hosmer ⁃ Lemeshow test value of this model was 4.230 (P = 0.836). The AUC value of the predictive model was 0.992 (95 % CI: 0.983 to 1.000), with a C-index of 0.992 (95 % CI: 0.983-1.000), indicating that the nomogram model had good accuracy and discrimination. Decision curve analysis showed that the nomogram model had a good predictive performance.

Conclusions

Age, preoperative albumin, duration of operation, and hospitalization time were independent influences on the occurrence of IAI in GSMT patients undergoing EFR surgery. A nomogram model based on these factors had a high predictive efficacy and may provide a guiding intervention for the prevention of postoperative IAI in GSMT patients.

A novel technique for endoscope progression in gastroscopy resection: forward-return way for dissection of stromal tumor in the muscularis propria of the gastric fundus

Background

The fundus of the stomach is a challenging region for endoscopic resection of gastrointestinal stromal tumors (GISTs), especially in the anterior wall of the fornix at the side of the greater curvature. This study aimed to introduce the Forward-Return Way (FRW) technique in gastric fundus operations and provide evidence of its advantages. The FRW technique allows the gastroscope to access the stomach fornix without entering the gastric antrum after passing through the gastric cardia. Using FRW, the gastroscope body makes a forward return along the wall of the posterior wall of the upper gastric body and the wall of the greater curvature.

Methods

The clinical data of patients with stromal tumors in muscularis propria at the gastric fundus (STMF) at the Fourth Hospital of China Medical University between May 2020- March 2021 were reviewed. The novel FRW technique was used in the procedures, and the beneficial effects, suitability, applicable lesion site, and success rates of FRW were analyzed.

Results

A total of 10 cases were reviewed, and the FRW technique was successfully performed in 7 cases (70%). The gastroscope's tip reached the area just below the gastric cardia, allowing endoscopists to successfully access all angles and sites of the stomach's fundus in all seven patients. The lesion was easily accessed, and the gastroscope was stable with good left-right and forward-backwards movements.

Conclusion

The FRW technique significantly facilitates the resection of the GISTs by aligning the endoscopy body movement direction with the observation direction. Gastrointestinal Stromal Tumor; forward-return of gastroscopy along the gastric body wall; muscularis propria; gastric fundus.

Efficacy and feasibility of snare-assisted endoscopic resection of small submucosal gastric tumors: A retrospective analysis

Background and aim

The prevalence of small submucosal gastric tumors is rising. Despite the fact that high success rate of endoscopic resection of small submucosal gastric tumors originating from the muscularis propria has been reported, the procedure is technically challenging and has a high rate of complications. In this study, we investigated the efficacy and feasibility of a novel snare-assisted endoscopic resection technique for small submucosal gastric tumors.

Patients and methods

This is a single-center consecutive study of 50 patients who were diagnosed with small submucosal gastric tumors originating from the muscularis propria and who subsequently underwent snare-assisted endoscopic resection between January 2019 and January 2021 at our hospital. Data on the demographic characteristics, procedural success rate, complications, recurrence rate, and histopathology of the resected specimen were collected and analyzed retrospectively.

Results

The majority of the patient’s population was male (66%) with the mean age of 48.4 ± 9 years (range, 20–70 years). The mean size of the tumor confirmed by endoscopic ultrasonography was 6.4 ± 1.6 mm (range, 3.1–9.8 mm). All the tumors were resected successfully using snare-assisted endoscopic resection technique. The mean procedure time was 22.8 ± 9.6 (range, 15–35 min). The technical (performed the procedure successfully without converting to surgery) and clinical (the patient fully recovered after the procedure without experiencing any complications) success rate of the procedure was 100%. Eighteen (24%) patients had very small amount of mucosal damage, and wound closure was not needed in these patients. During 6–24 months of follow-up, no recurrence or metastasis occurred. No adverse event was noted during the follow-up time.

Conclusion

The novel approach of snare-assisted endoscopic resection is simple, feasible, and effective for tumors with small size and originating from the gastric muscularis propria. In addition, it offers a better alternative therapy for the complete resection of small submucosal gastric tumors. Its advantages compared with traditional endoscopic approaches such as endoscopic submucosal resection and endoscopic submucosal dissection include shorter procedure times, lesser cost, and a lower rate of complications (perforation, bleeding, and infection).

Diagnosis of gastric submucosal tumors and estimation of malignant risk of GIST by endoscopic ultrasound. Comparison between B mode and contrast-harmonic mode

BACKGROUND

standard B-mode EUS assessment and EUS-guided tissue acquisition present sub-optimal diagnostic yield in the differential diagnosis of gastric submucosal tumors (SMTs).

AIMS

to evaluate the performances of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) to differentiate gastric SMTs and predict malignancy risk of gastrointestinal stromal tumors (GIST).

METHODS

a retrospective analysis was performed retrieving consecutive patients with gastric SMTs who underwent EUS between 2009 and 2014. Patients with available EUS video recordings and histological diagnosis were included. De-identified videos were presented to experts who made a diagnosis on B-mode EUS and CH-EUS.

RESULTS

fifty-four patients (29 female, 64-year-old) were included. Final diagnoses were 40 GISTs (8 high-grade), 9 leiomyomas, 5 rare SMTs. The sensitivity, specificity, and accuracy of B-mode and CH-EUS for the differential diagnosis of GIST were 95.0% vs. 85.0%, 57.1% for both techniques, and 85.2% vs. 77.8%, respectively. The sensitivity, specificity, and accuracy of B-mode and CH-EUS for the estimation of the malignancy GISTs risk were 62.5% vs. 100%, 83.3% vs. 82.1%, and 78.9% vs. 86.1%, respectively.

CONCLUSIONS

CH-EUS showed better diagnostic performance than B-mode EUS in differentiating leiomyomas and risk stratification of GIST. When considering high-grade GISTs, the addition of CH-EUS allowed an improvement in diagnostic accuracy.

Advancements in the Diagnosis of Gastric Subepithelial Tumors

A diagnosis of subepithelial tumors (SETs) is sometimes difficult due to the existence of overlying mucosa on the lesions, which hampers optical diagnosis by conventional endoscopy and tissue sampling with standard biopsy forceps. Imaging modalities, by using computed tomography and endoscopic ultrasonography (EUS) are mandatory to noninvasively collect the target's information and to opt candidates for further evaluation. Particularly, EUS is an indispensable diagnostic modality for assessing the lesions precisely and evaluating the possibility of malignancy. The diagnostic ability of EUS appears increased by the combined use of contrast-enhancement or elastography. Histology is the gold standard for obtaining the final diagnosis. Tissue sampling requires special techniques to break the mucosal barrier. Although EUS-guided fine-needle aspiration (EUS-FNA) is commonly applied, mucosal cutting biopsy and mucosal incision-assisted biopsy are comparable methods to definitively obtain tissues from the exposed surface of lesions and seem more useful than EUS-FNA for small SETs. Recent advancements in artificial intelligence (AI) have a potential to drastically change the diagnostic strategy for SETs. Development and establishment of noninvasive methods including AI-assisted diagnosis are expected to provide an alternative to invasive, histological diagnosis.