Endoscopic resection for calcifying fibrous tumors of the gastrointestinal tract.

BACKGROUND: Calcifying fibrous tumors (CFTs) are rare mesenchymal lesions that can occur in various sites throughout the body, including the tubular gastrointestinal (GI) tract. AIM: To analyze the clinical findings of 36 patients with GI tract CFTs to provide guidance for diagnosis and treatment. METHODS: This retrospective study included 36 patients diagnosed with CFTs of the GI tract. We collected demographic and clinical information and conducted regular follow-ups to assess for local recurrence. RESULTS: The stomach was the most commonly involved site, accounting for 72.2% of the 36 CFTs. Endoscopic mucosal resection (n = 1, 2.8%), endoscopic submucosal dissection (n = 14, 38.9%), endoscopic full-thickness resection (n = 16, 44.4%), and submucosal tunneling endoscopic resection (n = 5, 13.9%) were used to resect calcifying fibrous tumors. Overall, 34 (94.4%) CFTs underwent complete endoscopic resections with a mean procedure time of 39.8 ± 29.8 min. The average maximum diameter of the tumors was 10.6 ± 4.3 cm. No complications, such as bleeding or perforation, occurred during an average hospital stay of 2.9 ± 1.2 d. In addition, two patients developed new growth of CFTs near the primary tumor sites, and none of the patients developed distant metastases during the follow-up period. CONCLUSION: GI tract CFTs are rare and typically benign tumors that can be effectively managed with endoscopic procedures.

Feasibility and safety of endoscopic resection for the jejunoileal lesions.

BACKGROUND: Endoscopic resection (ER) for jejunoileal lesions (JILs) has been technically challenging. We aimed to characterize the clinicopathologic characteristics, feasibility, and safety of ER for JILs. METHOD: We retrospectively investigated 52 patients with JILs who underwent ER from January 2012 to February 2022. We collected and analyzed clinicopathological characteristics, procedure-related parameters, outcomes, and follow-up data. RESULTS: The mean age was 49.4 years. Of the 52 JILs, 33 ileal tumors within 20 cm from the ileocecal valve were resected with colonoscopy, while 19 tumors in the jejunum or the ileum over 20 cm from the ileocecal valve received enteroscopy resection. The mean procedure duration was 49.0 min. The en bloc resection and en bloc with R0 resection rates were 86.5% and 84.6%, respectively. Adverse events (AEs) included one (1.9%) major AE (delayed bleeding) and five (9.6%) minor AEs. During a median follow-up of 36.5 months, two patients had local recurrence (3.8%), while none had metastases. The 5-year recurrence-free survival (RFS) and disease-specific survival (DSS) were 92.9% and 94.1%, respectively. Compared with the enteroscopy group, overall AEs were significantly lower in the colonoscopy group (P < 0.05), but no statistical differences were observed in RFS (P = 0.412) and DSS (P = 0.579). There were no significant differences in AEs, RFS, and DSS between the endoscopic submucosal dissection (ESD) and the endoscopic mucosal resection (EMR) group. CONCLUSIONS: ER of JILs has favorable short-term and long-term outcomes. Both ESD and EMR can safely and effectively resect JILs in appropriately selected cases.

Endoscopic management of duodenal perforation caused by foreign bodies in adults: A retrospective study.

BACKGROUND AND AIMS: Duodenal perforation caused by foreign bodies (FBs) is very rare but is an urgent emergency that traditionally requires surgical intervention. Several case reports have reported the successful endoscopic removal of duodenal perforating FBs. Here we aimed to evaluate the safety and efficacy of endoscopic management of duodenal perforating FBs in adults. METHODS: Between October 2004 and October 2022, 12,851 patients with endoscopically diagnosed gastrointestinal FBs from four tertiary hospitals in China were retrospectively reviewed. Patients were enrolled if they were endoscopically and/or radiographically diagnosed with duodenal perforating FBs. RESULTS: The incidence of duodenal total FBs and perforating FBs was 1.9% and 0.3%, respectively. Thirty-four patients were enrolled. Endoscopic removal was achieved in 25 patients (73.5%), and nine patients (26.5%) received surgery. For the endoscopic group, most perforating FBs were located in the duodenal bulb (36.0%) and descending part (28.0%). The adverse events included 3 mucosal injuries and 1 localized peritonitis. All patients were cured after conventional treatment. In the surgical group, most FBs were lodged in the descending part (55.6%). One patient developed localized peritonitis and one patient died of multiple organ failure. The significant features of FBs requiring surgery included FB over 10 cm, both sides perforation, multiple perforating FBs and massive pus overflow. CONCLUSION: Endoscopic removal of duodenal perforating FBs is safe and effective, and can be the first choice of treatment for experienced endoscopists. Surgical intervention may be required for patients with FBs over 10 cm, both sides perforation, multiple perforating FBs, or severe infections.

Management of delayed bleeding of upper gastrointestinal endoscopic submucosal tunneling procedures: a retrospective single-center analysis and brief meta-analysis.

OBJECTIVES: Delayed bleeding is a rare but important major adverse event (mAE) after endoscopic submucosal tunneling procedures (ESTP), which is scarcely reported. We aimed to characterize the clinical characteristics of delayed bleeding and provide better management of this mAE. METHOD: From August 2010 to October 2022, we reviewed 3852 patients with achalasia receiving peroral endoscopic myotomy (POEM) and 1937 patients with upper gastrointestinal tumors receiving submucosal tunneling endoscopic resection (STER). Among these, records of 22 patients (15 POEM, 7 STER) with delayed bleeding were collected. Clinical characteristics, treatment, and outcomes of delayed bleeding were analyzed. RESULTS: The mean age was 43.6 years. Ten patients (45.5%) were intratunnel bleeding, seven (31.8%) were intratunnel bleeding accompanied by mucosal bleeding, and five (22.7%) were mucosal bleeding. The most common accompanied symptoms were hematemesis, fever, and melena. The most common accompanied mAEs were fistula, pulmonary inflammation, and pleural effusion with atelectasis. The mean duration from ESTP to endoscopic intervention was 5.3 ± 4.9 days. Active bleeding was identified in 21 patients (95.5%). The bleeding was successfully controlled by electrocoagulation (19 cases), endoscopic clipping (six cases), and Sengstaken-Blakemore tube insertion (three cases), and no patient required surgical intervention. The mean hemostatic procedure duration was 61.8 ± 45.8 min. The mean post-bleeding hospital stay was 10.0 ± 6.2 days. A brief meta-analysis of previous studies showed the pooled estimate delayed bleeding rate after POEM, STER, and G-POEM was 0.4%. CONCLUSIONS: Delayed bleeding is uncommon and could be effectively managed by timely emergency endoscopic procedures without requiring subsequent surgical interventions.

Landscape of Psychological Profiles in Patients With Esophageal Achalasia.

INTRODUCTION: Esophageal achalasia (EA) is a chronic esophageal dysmotility disease, of which psychological distress was poorly understood. This study aims to assess the status of psychosocial characteristics in EA and to determine the relationship between psychological distress and EA. METHODS: Seventy pairs of age and gender-matched patients with EA and healthy control individuals were prospectively enrolled from December 2019 to April 2020 at our hospital. Demographic, psychosocial, and clinical data were obtained. Psychosocial assessments contained psychological distress (Symptom Checklist-90 Revised), perceived stress (Perceived Stress Scale-14), and stressful life events (Life Events Scale). Comparison for psychological parameters was made between patients with EA and controls as well as for EA before/after per oral endoscopic myotomy (POEM). Spearman rank correlation coefficients were used to testify the association between psychological distress and achalasia symptoms. RESULTS: The mean course and Eckardt score of patients with EA were 4.26 ± 5.11 years and 6.63 ± 2.21, respectively. There was a significant difference between patients with EA and healthy individuals in Global Severity Index ( P = 0.039) and Positive Symptoms Total ( P = 0.041) for Symptom Checklist-90 Revised as well as positive intensity ( P = 0.011) for the Life Events Scale. Somatization ( P < 0.001), anxiety ( P = 0.021), anger-hostility ( P = 0.009), and others (appetite and sleep, P = 0.010) accounted for the most difference. Somatization was positively associated with chest pain ( P = 0.045). Two patients with EA developed recurrence and showed no relationship with psychological status. Psychological status was significantly improved after POEM. DISCUSSION: Psychological distress, especially somatization, was more prevalent in patients with EA than healthy controls. POEM seemed able to improve psychological distress.

Muscular injury as an independent risk factor for esophageal stenosis after endoscopic submucosal dissection of esophageal squamous cell cancer.

BACKGROUND AND AIMS: Stenosis after esophageal endoscopic submucosal dissection (ESD) has a high incidence, and muscular injury is an important risk factor for esophageal stenosis. Hence, this study aimed to classify muscular injury degrees and investigate their association with postoperative stenosis. METHODS: This retrospective study included 1033 patients with esophageal mucosal lesions treated with ESD between August 2015 and March 2021. Demographic and clinical parameters were analyzed, and stenosis risk factors were identified using multivariate logistic regression. A novel muscular injury classification system was proposed and used to investigate the association between different muscular injury degrees and postoperative stenosis. Finally, a scoring system was established to predict muscular injury. RESULTS: Of 1033 patients, 118 (11.4%) had esophageal stenosis. The multivariate analysis demonstrated that the history of endoscopic esophageal treatment, circumferential range, and muscular injury were significant risk factors for esophageal stenosis. Patients with type II muscular injuries tended to develop complex stenosis (n = 13 [36.1%], P < .05), and type II muscular injuries were more likely to predispose patients to severe stenosis than type I (73.3% and 92.3%, respectively). The scoring system showed that patients with high scores (3-6) were more likely to have muscular injury. The score model presented good discriminatory power in the internal validation (area under the receiver-operating characteristic curve, .706; 95% confidence interval, .645-.767) and goodness-of-fit in the Hosmer-Lemeshow test (P = .865). CONCLUSIONS: Muscular injury was an independent risk factor for esophageal stenosis. The scoring system demonstrated good performance in predicting muscular injury during ESD.

Salvage peroral endoscopic myotomy is a promising treatment for achalasia after myotomy failure.

BACKGROUND AND AIMS: Reintervention modalities after myotomy failure in achalasia patients have yet to be established. The efficacy and safety of salvage peroral endoscopic myotomy (POEM) for treatment of achalasia after myotomy failure were evaluated in the study. METHODS: Between August 2011 and August 2021 at the Endoscopy Center of Zhongshan Hospital, 219 achalasia patients who had previously undergone a myotomy underwent a salvage POEM and were thus retrospectively enrolled in this study. After propensity score matching (PSM), operation-related parameters were compared between the salvage POEM group and the naïve POEM group. Subgroup analysis was performed between patients with previous Heller myotomy (HM) and patients with previous POEM. RESULTS: With similar baseline characteristics between both groups after PSM, the salvage POEM group presented with shorter tunnel length (11.8 ± 2.2 cm vs 12.8 ± .9 cm, P < .0001) and myotomy length (9.8 ± 2.0 cm vs 10.4 ± 1.0 cm, P < .0001) than the naïve POEM group. No significant differences were found in procedure-related adverse events between patients of salvage POEM and naïve POEM. The primary outcome of treatment success occurred in 175 of 193 patients (90.7%) in the salvage POEM group versus 362 of 374 patients (96.8%) in the naïve POEM group (P = .0046). At a 2- and 5-year follow-up, significantly higher rates of clinical failures were observed in the previous HM subgroup than in the previous POEM subgroup (P = .0433 and P = .0230, respectively). CONCLUSIONS: Salvage POEM after a previous myotomy failure, especially after a POEM failure, is a promising treatment option because it has a durable clinical relief rate.

Clinical outcomes of endoscopic resection for the treatment of esophageal gastrointestinal stromal tumors: a ten-year experience from a large tertiary center in China.

BACKGROUNDS: Esophageal gastrointestinal stromal tumors (E-GISTs) are extremely rare and surgical resection is the recommended approach. However, surgical resection usually causes severe trauma that may result in significant postoperative morbidity. Endoscopic resection (ER) has developed rapidly in recent years and has been widely used in gastrointestinal lesions. Nevertheless, the feasibility and efficacy of ER in the management of E-GISTs are unknown. METHODS: Retrospective data were collected from January 2011 to December 2020 in a large tertiary center of China. Twenty-eight patients with E-GISTs treated by ER were included in the study. RESULTS: Of the 28 patients, there were 21 males and 7 females, with a median age of 55 years (40-70 years). The median tumor size was 15 mm (5-80 mm). The technical success rate was 100% (28/28), while the en bloc resection rate was 96.4% (27/28). The median operation time was 35 min (10-410 min). Sixteen (57.2%) tumors were categorized into very low risk group, six (21.4%) into low risk group, and six (21.4%) into high risk group. Pathologists carefully examined margins of each lesion. There were 11 lesions (39.3%) determined as R0 resection and 17 lesions (60.7%) as R1 resection with positive margins. The median hospital stay was 2 days (range, 1-8 days). One patient suffered from hydrothorax and required drainage, leading to a major adverse event rate of 3.6% (1/28). There was no conversion to surgery, and no death occurred within 30 days after the procedure. Imatinib was given to two patients after ER under multidisciplinary team surveillance. During follow-up (median of 54 months, 9-122 months), no recurrences or metastasis were observed. CONCLUSION: ER is safe and effective for E-GISTs and might become an optional choice in the future. Multicenter, prospective, large samples with long-term follow-up studies are still needed.

Single-cell transcriptomic analysis deciphers key transitional signatures associated with oncogenic evolution in human intramucosal oesophageal squamous cell carcinoma.

BACKGROUND AND AIMS: The early diagnosis and intervention of oesophageal squamous cell carcinoma (ESCC) are particularly important because of the lack of effective therapies and poor prognosis. Comprehensive research on early ESCC at the single-cell level is rare due to the need for fresh and high-quality specimens obtained from ESD. This study aims to systematically describe the cellular atlas of human intramucosal ESCC. METHODS: Five paired samples of intramucosal ESCC, para-ESCC oesophageal tissues from endoscopically resected specimens and peripheral blood mononuclear cells were adopted for scRNA-seq analysis. Computational pipeline scMetabolism was applied to quantify the metabolic diversity of single cells. RESULTS: A total of 164 715 cells were profiled. Epithelial cells exhibited high intra-tumoural heterogeneity and two evolutionary trajectories during ESCC tumorigenesis initiated from proliferative cells, and then through an intermediate state, to two different terminal states of normally differentiated epithelial cells or malignant cells, respectively. The abundance of CD8+ TEX s, Tregs and PD1+ CD4+ T cells suggested an exhausted and suppressive immune microenvironment. Several genes in immune cells, such as CXCL13, CXCR5 and PADI4, were identified as new biomarkers for poor prognosis. A new subcluster of malignant cells associated with metastasis and angiogenesis that appeared at an early stage compared with progressive ESCC was also identified in this study. Intercellular interaction analysis based on ligand-receptor pairs revealed the subcluster of malignant cells interacting with CAFs via the MDK-NCL pathway, which was verified by cell proliferation assay and IHC. This indicates that the interaction may be an important hallmark in the early change of tumour microenvironment and serves as a sign of CAF activation to stimulate downstream pathways for facilitating tumour invasion. CONCLUSION: This study demonstrates the changes of cell subsets and transcriptional levels in human intramucosal ESCC, which may provide unique insights into the development of novel biomarkers and potential intervention strategies.

Endoscopic resection of upper GI extraluminal tumors (with videos).

BACKGROUND AND AIMS: Endoscopic resection is a feasible treatment for GI extraluminal tumors but remains a challenging procedure with limited data. In this study, we assessed the safety and efficacy of endoscopic resection for extraluminal tumors in the upper GI tract. METHODS: From May 2016 to December 2021, 109 patients undergoing endoscopic resection for extraluminal tumors in the upper GI tract were retrospectively included. Clinicopathologic characteristics, procedure-related parameters, adverse events (AEs), and follow-up outcomes were analyzed. RESULTS: The en-bloc tumor resection rate was 94.5% and en-bloc retrieval rate 86.2%. Statistical analysis revealed tumor size ≥3.0 cm and irregular shape as significant risk factors for piecemeal extraction. Resection time and suture time were 46.8 ± 33.6 minutes and 20.6 ± 20.1 minutes, respectively. Large tumor size was significantly associated with a longer procedure duration. Five patients (4.6%) experienced major AEs, including recurrent laryngeal nerve injury, hydrothorax, major bleeding, local peritonitis, duodenal leakage, and repeat endoscopic surgery for tumor extraction. Minor AEs occurred in 13 patients (11.9%). Irregular tumor shape and tumor location (duodenum) were significantly associated with AE occurrence. Mean postoperative hospital stay was 4.7 ± 3.3 days. No recurrence or metastasis was observed during the mean follow-up period of 31.8 ± 15.2 months. CONCLUSIONS: Endoscopic resection is a safe and feasible therapeutic approach for upper GI extraluminal tumors. Tumor size, shape, and location impact the difficulty and safety of the procedure. Endoscopic resection of duodenal tumors is also feasible but associated with an increased risk of AEs compared with tumors in other locations.

Erratum: A scoring system to support surgical decision-making for cardial submucosal tumors.

[This corrects the article DOI: 10.1055/a-1775-7976.].

A scoring system to support surgical decision-making for cardial submucosal tumors.

Background and study aims Submucosal tunneling endoscopic resection (STER) and non-tunneling techniques are two alternative options for the treatment of cardial submucosal tumors (SMTs). We aimed to establish a regression model and develop a simple scoring system (Zhongshan Tunnel Score) to help clinicians make surgical decisions for cardial submucosal tumors. Patients and methods A total of 246 patients who suffered cardial SMTs and received endoscopic resection were included in this study. All of them were randomized into either the training cohort (n = 147) or the internal validation cohort (n = 99). Then, the scoring system was proposed based on multivariate logistic regression analysis in the training cohort and assessed in the validation cohort. Results Of 246 patients, 97 were treated with STER and the others with non-tunneling endoscopic resection. In the training stage, four factors were weighted with points based on the ß coefficient from the regression model, including irregular morphology (-2 points), ulcer (2 points), the direction of the gastroscope (-2 points for forward direction and 1 point for reverse direction), and originating from the muscularis propria (-2 points). The patients were categorized into low-score (< -4), medium-score (-4 to -3) and high-score (> -3) groups, and those with low scores were more likely to be treated with STER. Our score model performed satisfying discriminatory power in internal validation (Area under the receiver-operator characteristic curve, 0.829; 95 % confidence interval, 0.694-0.964) and goodness-of-fit in the Hosmer-Lemeshow test ( P  = .4721). Conclusions This scoring system could provide clinicians the references for making decisions about the treatment of cardial submucosal tumors.

Landscape of esophageal submucosal tunneling endoscopic resection-related adverse events in a standardized lexicon: a large volume of 1701 cases.

BACKGROUND: Submucosal tunneling endoscopic resection (STER) has been widely applied for esophageal submucosal tumors. This large volume study aims to provide a standard landscape of STER-related AEs for reference. METHODS: 1701 patients with esophageal SMTs undergoing STER were included at Zhongshan Hospital, Fudan University. Data of clinical characteristics and adverse events were collected and analyzed in depth. Adverse events were recorded by ASGE lexicon and graded by ASGE grading/Clavien-Dindo system. Risk factors for major AEs were analyzed by univariate and multivariate logistic regression. RESULTS: Three hundred and twenty (18.8%) patients with 962 cases of adverse events were observed. Accordingly, 84 (5.0%) were classified as major AEs (moderate and severe) by ASGE grading and 37 (2.2%) were classified as major AEs (grades III-V) by Clavien-Dindo grading. First 1 year operation, distance > 6 cm from incision to tumor, piecemeal resection, partially extraluminal location, mucosal injury, and operation time > 60 min were included in the risk score model for major AEs of STER, with 57.1% sensitivity and 87.5% specificity. CONCLUSIONS: STER was a safe procedure for diagnosis and treatment of esophageal SMTs with a total 18.8% incidence of AEs, among which only 5.0% were major AEs requiring therapeutic measurements.

Repeat endoscopic submucosal dissection as salvage treatment for local recurrence of esophageal squamous cell carcinoma after initial endoscopic submucosal dissection.

BACKGROUND AND AIMS: Local recurrence of esophageal squamous cell carcinoma (ESCC) after endoscopic resection does not have an established treatment. The efficacy and safety of repeat endoscopic submucosal dissection (ESD) for recurrent ESCC were determined in the study. METHODS: Forty-three consecutive patients with 45 locally recurrent superficial ESCC lesions undergoing repeat ESD and 909 first ESD lesions for propensity score matching (PSM) at Zhongshan Hospital between January 2011 and January 2020 were retrospectively enrolled. After PSM (1:2), operation-related parameters were compared between repeat ESD and first ESD. In the repeat ESD group, the Kaplan-Meier method and log-rank tests were used for identification of risk factors for local recurrence after repeat ESD. RESULTS: As compared with propensity score-matched first ESD, rates of complete resection (86.7% vs 97.8%, P = .02) and curative resection (86.7% vs 96.7%, P = .06) were lower and procedure duration (54.8 ± 21.7 minutes vs 46.2 ± 20.6 minutes, P = .67) and hospital stay (4.3 ± 1.8 days vs 2.9 ± 1.4 days, P = .25) were longer in the repeat ESD group. The en-bloc resection rate (93.3% vs 98.8%, P > .11) remained comparable. Adverse events including bleeding (4.4% vs 0%, P = .11), perforation (.0% vs .0%, P > .99), and stricture (6.7% vs 2.2%, P = .33) presented with no difference. The 5-year overall survival rate and recurrence-free survival rate for repeat ESD was 100% and 86.0%, respectively. Multiplicity was significantly associated with recurrence after repeat ESD (P = .01). CONCLUSIONS: Repeat esophageal ESD showed favorable short- and long-term outcomes and thus provides an alternative choice for recurrent superficial ESCC.

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.

Long-term prognosis of small gastric gastrointestinal stromal tumors with high histological grade: a longitudinal nested cohort study.

BACKGROUND AND AIMS: Gastrointestinal stromal tumors (GIST) are mostly seen in the stomach. Clinical data on GISTs ≤ 2 cm with > 5 mitosis/50 HPFs are limited. This study aimed to analyze small GISTs with high histological grades to gain a more comprehensive understanding of their clinical characteristics with long-term follow-up. METHODS: This was a nested cohort study of patients with gastric GISTs ≤ 2 cm and > 5 mitosis/50 HPFs. Individuals with endoscopically resected gastric specimens diagnosed as GISTs between January 2008 and July 2019 were enrolled. We analyzed baseline clinicopathological characteristics, perioperative characteristics, risk of recurrence, and metastasis during follow-up. RESULTS: A total of 55 patients diagnosed with gastric GISTs ≤ 2 cm and > 5 mitosis/50 HPFs were enrolled. The mean tumor size was 1.6 ± 0.4 cm (median 1.7 cm, range 0.8-2.0 cm). ESD was performed in 33 patients (60.0%) and EFTR in 22 patients (40.0%). Mean mitotic figures were 8.9/50 HPFs. Postoperative bleeding in one patient (1.8%) was the only severe adverse event. The mean follow-up period was 61.2 ± 33.9 months (median 53 months, range 13-133 months). Five patients (5/55, 9.1%) received additional therapies, including partial gastrectomy and adjuvant Imatinib. Only two patients (2/55, 3.6%) showed signs of recurrence. We observed no significant difference regarding baseline clinical characteristics and recurrence among GISTs with mitosis < 10/50 HPF and ≥ 10/50 HPF. No patient had signs of metastasis during follow-up. CONCLUSION: Endoscopic resection of gastric GISTs ≤ 2 cm with > 5 mitosis/50 HPFs has a low risk of recurrence and metastasis in the long term. Endoscopic resection of GISTs is safe and feasible.