Mucosal Incision and Forceps Biopsy for Reliable Tissue Sampling of Gastric Subepithelial Tumors

Diagnostic ability and adverse events of mucosal incision-assisted biopsy for gastric subepithelial tumors: Systematic review and meta-analysis

OBJECTIVES

This systematic review and meta-analysis aimed to evaluate the diagnostic ability and examine the efficacy of countermeasures to adverse events of mucosal incision-assisted biopsy (MIAB) for gastric subepithelial tumors (SETs).

METHODS

We performed a literature search and identified 533 relevant articles. Eleven articles, including 339 lesions, were ultimately used in the meta-analysis. The primary end-point was the pathological diagnostic rate of MIAB for gastric SETs, and the secondary end-point was the incidence of adverse events. The efficacy of acid secretion inhibitors in preventing postoperative bleeding and that of local injection before incision to prevent perforation were also examined.

RESULTS

Nine studies were conducted in Japan and two in South Korea, of which only two were prospective studies. The pooled pathological diagnostic rate of MIAB for gastric SETs was 87.8% (95% confidence interval [CI] 80.2-94.0; I2 = 68.7%). The adverse event rate of the pooled population was 0.2% (95% CI 0-1.4; I2 = 0%). The acid secretion inhibitors significantly reduced postoperative bleeding (odds ratio 0.06, 95% CI 0.01-0.66, P = 0.02). Perforation occurred in 0% and 2.6% of the local and nonlocal injection cohorts, respectively, and the pathological diagnostic rates were 50% and 66.7%, respectively.

CONCLUSIONS

MIAB is a reliable technique with a favorable diagnostic rate and few adverse events. Acid secretion inhibitors may effectively prevent postoperative bleeding; however, the efficacy of local injection remains unclear. This technique could be an option for tissue sampling in gastric SETs.

Diagnostic yield of endoscopic and EUS-guided biopsy techniques in subepithelial lesions of the upper GI tract: a systematic review

BACKGROUND AND AIMS

Obtaining adequate tissue samples in subepithelial lesions (SELs) remains challenging. Several biopsy techniques are available, but a systematic review including all available techniques to obtain a histologic diagnosis of SEL is lacking. The aim of this study was to evaluate the diagnostic yield and adverse event rates of endoscopic biopsies, EUS-guided FNA (EUS-FNA), EUS-guided fine-needle biopsy (FNB) (EUS-FNB), and mucosal incision-assisted biopsy (MIAB) for SELs in the upper GI tract.

METHODS

A search strategy in multiple databases was performed. The primary outcome was diagnostic yield, defined as the percentage of procedures in which histology was obtained and resulted in a definitive histopathologic diagnosis. Secondary outcome measures included reported procedure-related adverse events, which were graded according to the AGREE (Adverse Events in Gastrointestinal Endoscopy) classification.

RESULTS

A total of 94 original articles were included. Studies were classified per endoscopic technique to obtain histopathology. This resulted in 8 included studies for endoscopic biopsy methods, 55 studies for EUS-FNA, 33 studies for EUS-FNB, and 26 studies for MIAB. Pooled rates for diagnostic yield were 40.6% (95% confidence interval [CI], 30.8-51.2) for endoscopic biopsy, 74.6% (95% CI, 69.9-78.7) for EUS-FNA, 84.2% (95% CI, 80.7-87.2) for EUS-FNB, and 88.2% (95% CI, 84.7-91.1) for MIAB. Reported procedure-related adverse events graded AGREE II or higher were 2.8% to 3.9% for endoscopic biopsies, 1.0% to 4.5% for EUS-FNA, .9% to 7.7% for EUS-FNB, and 1.9% to 7.9% for MIAB.

CONCLUSIONS

Based on the available evidence, MIAB and EUS-FNB seem to be most effective in terms of achieving a high diagnostic yield, with similar rates of adverse events.

Natural history of gastric leiomyoma

BACKGROUND

Most gastric leiomyomas are asymptomatic and benign subepithelial tumors (SETs); however, some may increase in size or become symptomatic. Understanding their natural history is therefore important to their management. We investigated the natural history of histologically proven gastric leiomyomas.

METHODS

We retrospectively reviewed histologically proven gastric leiomyoma cases at a tertiary center. The baseline characteristics of these cases were analyzed, and those with a follow-up period of at least 12 months without immediate resection were evaluated. The primary outcome was the frequency of size increase of more than 25% during the follow-up period, and the secondary outcome was the histopathologic results in cases that underwent resection.

RESULTS

Among the 231 patients with histologically proven gastric leiomyomas, the most frequent location was the cardia (77.1%), and the median size was 3 cm (IQR 2-4 cm). Eighty-four cases were followed up over a median period of 50.8 months (IQR 27.2-91.3 months). During the follow-up period, tumor size increased in two cases (2.4%). Surgical results showed that one case was leiomyoma, and the other was leiomyosarcoma. Among the remaining cases without change in size, 15 underwent surgical resection (n = 10) or endoscopic resection (n = 5), and all cases were confirmed as leiomyoma.

CONCLUSIONS

Most gastric leiomyomas are benign SETs, and an increase in size is not frequent, even in large-sized cases. Close monitoring with routine follow-up without resection may be sufficient in cases of histologically proven gastric leiomyoma. However, in cases of ulceration or size increase, resection may be beneficial.

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.

Clinical efficacy and safety of mucosal incision-assisted biopsy for the diagnosis of upper gastrointestinal subepithelial tumors: A systematic review and meta-analysis

Background

Endoscopic ultrasound-guided fine-needle aspiration and biopsy (EUS-FNA/FNB) has been traditionally used for making a tissue diagnosis. Several newer techniques are emerging as a viable alternative to EUS-FNA/FNB, including mucosal incision-assisted biopsy (MIAB), with a view to increasing the diagnostic yield for upper gastrointestinal (GI) subepithelial tumors (SETs). We conducted a systematic review and meta-analysis to describe the overall diagnostic yield of MIAB for upper GI SETs.

Methods

Multiple electronic databases (MEDLINE, EMBASE and Google Scholar) and conference abstracts were comprehensively searched. The primary outcome of our meta-analysis was the overall diagnostic yield of the MIAB. The secondary outcome was to study complications in terms of perforation and clinically significant bleeding. The meta-analysis was performed using a DerSimonian and Laird random-effect model.

Results

Seven studies were included in the final meta-analysis, reporting a total of 159 patients (male 86, female 73) with a mean age of 58 years. The overall pooled diagnostic yield of MIAB was 89% (95% confidence interval [CI] 82.65-93.51, I ²=0.00). Histologically, GI stromal tumor was the reported diagnosis in 38.62% (95%CI 22.29-56.24, I ²=77.51%) of tumors, followed by leiomyoma 25% (95%CI 18.02-32.62, I ²=4.42%). The overall rate of clinically significant bleeding following the procedure was 5.03% (95%CI 0.36-12.86, I ²=57.43%) and no perforations were reported.

Conclusions

MIAB is a safe and effective technique for the diagnosis of upper GI SETs and can be considered as a viable alternative to EUS-FNA/FNB. MIAB can be performed during routine endoscopy and no advanced equipment is required.

Comparison of the Diagnostic Ability of Endoscopic Ultrasonography and Abdominopelvic Computed Tomography in the Diagnosis of Gastric Subepithelial Tumors

Background/Aims

Endoscopic ultrasonography (EUS) is the most efficient imaging modality for gastric subepithelial tumors (SETs). However, abdominopelvic computed tomography (APCT) has other advantages in evaluating the characteristics, local extension, or invasion of SETs to adjacent organs. This study aimed to compare the diagnostic ability of EUS and APCT based on surgical histopathology results.

Methods

We retrospectively reviewed data from 53 patients who underwent both EUS and APCT before laparoscopic wedge resection for gastric SETs from January 2010 to December 2017 at a single institution. On the basis of histopathology results, we assessed the diagnostic ability of the 2 tests.

Results

The overall accuracy of EUS and APCT was 64.2% and 50.9%, respectively. In particular, the accuracy of EUS vs. APCT for the diagnosis of gastrointestinal stromal tumors (GISTs), leiomyomas, and ectopic pancreas was 83.9% vs. 74.2%, 37.5% vs. 0.0%, and 57.1% vs. 14.3%, respectively. Most of the incorrect diagnoses with EUS involved hypoechoic lesions originating in the fourth echolayer, with the most common misdiagnosed lesions being GISTs mistaken for leiomyomas and vice versa.

Conclusions

APCT showed a lower overall accuracy than EUS; however, APCT remains a useful modality for malignant/potentially malignant gastric SETs.

Endoscopic full-thickness resection of gastric subepithelial tumors with the gFTRD-system: a prospective pilot study (RESET trial)

BACKGROUND

Gastric subepithelial tumors (SET) are rare and usually benign. However, up to 13% are malignant. Histology after conventional biopsy often is inconclusive. Surveillance endoscopies are the consequence in the majority of gastric SET cases. For SET arising from deeper layers endoscopic resection (ER) with the standard techniques is difficult and associated with the risk of perforation. The RESET trial further evaluates feasibility, efficacy and safety of clip-assisted endoscopic full-thickness resection (EFTR) for gastric SET using the novel gastric full-thickness-resection device (gFTRD).

MATERIALS AND METHODS

The RESET trial was initiated in March 2017 (NCT03096236) and designed as prospective observational multicenter pilot trial. Gastric SET up to 15 mm were included. Primary endpoint was technical success (complete enbloc resection). Secondary endpoints were R0 resection, full-thickness resection, adverse events and recurrency at 3-months follow-up. For resection we used the gFTRD (Ovesco Endoscopy, Tübingen, Germany).

RESULTS

29 patients underwent gastric EFTR. Histology prior EFTR after conventional biopsy could define histological tumor type in only 31.2%. Primary endpoint was reached in 89.7%. Histology of the full-thickness-resection specimen could define histological tumor type in 100%. 76% of all SET could be resected histologically complete (R0) and a full-thickness-resection specimen could be obtained in 65.5%. In 31% periprocedural minor bleeding was observed and managed endoscopically. Follow-up was available in 79.3% (OTSC detachment in 78.3%, OTSC in position in 21.7%). No signs of residual or recurrent tumors were observed after 3 months.

CONCLUSION

EFTR of gastric SET with gFTRD is feasible and safe. EFTR allows a definite histological diagnosis (including sufficient risk stratification in case of GIST or NET) in contrast to conventional biopsy. R0-resection is possible in most cases and might obviate the need for further surveillance endoscopies for selected patients.