Endoscopic submucosal excavation and endoscopic full-thickness resection for gastric schwannoma: five-year experience from a large tertiary center in China. Surg Endosc. 2020;34:4943-4949. [PMID: 31811454 DOI: 10.1007/s00464-019-07285-w]

Endoscopic full-thickness resection of a large gastric schwannoma and iatrogenic cervical esophageal perforations: A case report

INTRODUCTION

Gastrointestinal schwannomas are most commonly found in the stomach. Owing to their nonspecific clinical and endoscopic presentations, distinguishing gastric schwannomas (GS) from other gastric submucosal tumors based on typical symptoms and endoscopic features is challenging. Endoscopic full-thickness resection (EFTR) is safe and effective for GS management; however, no standard method exists for the extraction of large gastric specimens after endoscopic treatment.

CASE PRESENTATION

We report the case of a 72-year-old Chinese woman who presented with abdominal distension.

DIAGNOSIS, INTERVENTIONS, AND OUTCOMES

Gastroscopy revealed a submucosal bulge on the anterior wall of the lower stomach near the greater curvature. Endoscopic ultrasonography and computed tomography suggested a stromal tumor. The patient underwent EFTR of the stomach, and the tumor was successfully removed. The surgical specimen, with a long-axis diameter of approximately 5.5 cm in vitro, was extracted using a snare. Subsequent endoscopic examination revealed longitudinal, full-thickness perforations > 2 cm at the esophageal entrance. Over 10 metal clips were used to seal the mucosa, and a gastrointestinal decompression tube was placed. Follow-up radiography performed at 1 week postoperatively revealed an esophageal mediastinal fistula, which required subsequent endoscopic intervention to close the fistula using metal clips. The patient showed improvement and was discharged at 3 weeks postoperatively. Follow-up esophageal radiography revealed no abnormalities. Postoperative immunohistochemical analysis indicated CD34 (-), CD117 (-), DOG-1 (-), Ki67 (1%), S-100 (+), SDHB (+), SOX-10 (+), and Desmin (-), confirming the diagnosis of GS. Three months postoperatively, gastroscopy showed that the esophageal perforation healed well, a white ulcer scar had formed locally, metal clips were found in the stomach body, and no recurrence was found.

CONCLUSION

EFTR is effective for removing giant schwannomas, although the extraction of large specimens may result in iatrogenic cervical esophageal perforations. Perforations > 2 cm can be managed using endoscopic metal clip closure.

Same duodenal neuroendocrine tumors, different endoscopic resection methods: a case report and literature review

Duodenal neuroendocrine tumors (NETs), comprising 2-3% of all gastrointestinal NETs and 1-3% of all duodenal tumors, are remarkably uncommon. In this report, we described a patient diagnosed with two submucosal tumors in the duodenal bulb. We used two distinct endoscopic resection methods, including endoscopic submucosal dissection (ESD) and submucosal tunneling endoscopic resection (STER), to achieve en bloc resection of the lesions without complications. Pathological evaluation, involving hematoxylin-eosin staining and immunohistochemistry, confirmed the diagnosis of NET. Given the limited operative field and space in the duodenal bulb, STER proved to be a viable endoscopic resection technique.

Efficacy and Safety of Endoscopic Resection for Gastric Gastrointestinal Stromal Tumors Originating from the Muscularis Propria

BACKGROUND

The role of endoscopic resection (ER) in gastric gastrointestinal stromal tumors (GISTs) has not been fully elucidated.

AIMS

The purpose of this work was to evaluate the clinical effectiveness and safety of ER in patients with GISTs originating from the muscularis propria (MP).

METHODS

A total of 233 consecutive patients with gastric GISTs originating from the MP layer, who underwent ER between February 2012 and May 2023, were included in this study. Clinical characteristics, tumor features, and outcomes were recorded and compared between patients who underwent en bloc resection and piecemeal resection.

RESULTS

Among the 233 patients, the median size of GISTs was 12 mm (range 5-60 mm). Risk assessment categorized 190 patients as very low risk, 26 as low risk, 10 as moderate risk, and 7 as high risk. The procedures performed included endoscopic submucosal excavation (127 cases), endoscopic full-thickness resection (103 cases), and submucosal tunneling endoscopic resection (3 cases). The complete and R0 resection rate was 93.1%. Complications occurred in 4.7% of cases (perioperative perforations 1.7%, perioperative bleeding 1.3%, both 0.9%), resulting in conversion to surgery in 1.3% of cases. Risk factors associated with piecemeal resection were tumor size [odds ratio (OR) 0.402, 95% confidence interval (CI) 0.207-0.783; P = 0.007] and shape (OR 0.045, 95% CI 0.009-0.235; P < 0.001).

CONCLUSIONS

ER is proven to be an effective and reasonably safe approach for gastric GISTs originating from the MP. Notably, larger tumor size and irregular shape are identified as risk factors for piecemeal resection during ER procedures.

The Outcome of Snare-Assisted Traction Endoscopic Full-Thickness Resection for the Gastric Fundus Submucosal Tumors Originating from the Muscularis Propria

Aim: To explore the feasibility and effectiveness of snare-assisted traction endoscopic full thickness resection (EFTR) on gastric fundus submucosal tumors (SMTs). Methods: The clinical and pathological data of patients with gastric SMTs who underwent EFTR treatment at the Endoscopy Center of Kaifeng Central Hospital from January 2018 to June 2023 were collected. Among them, 36 patients underwent snare-assisted traction EFTR (SAT-EFTR) and 46 patients underwent standard EFTR (S-EFTR). The clinical baseline data, operative data, adverse events, and follow-up results of the two groups were collected and compared. Results: All patients successfully completed EFTR technique. There were 34 male and 48 female patients, with an average age of (56.62 ± 11.31) years. The average operation time was shorter in the snare-assisted EFTR group than the S-EFTR group (73.39 ± 31.33 minutes versus 92.89 ± 37.57 minutes, P = .014). In addition, the resection speed of the snare-assisted EFTR group was also significantly faster than that of the S-EFTR group (4.04 ± 2.23 versus 2.48 ± 0.93 mm2/min, P < .001). There was no statistically significant difference in the age, gender, lesion size, postoperative fasting duration, and postoperative hospitalization stay between the two groups (P > .05). One patient in the SAT-EFTR group developed delayed postoperative perforation which was close with purse‑string suture technique. All patients were discharged successfully, and there was no recurrence or metastasis during the follow-up period. Conclusion: Snare-assisted traction of EFTR could shorten the operation time, reduce the difficulty of the operation, and improve the efficiency of the operation. At the same time, this method is simple and easy to learn, more suitable for beginners, and worthy of clinical promotion and application.

Gastric schwannoma: A retrospective analysis of clinical characteristics, treatments, and outcomes

BACKGROUND

This study aimed to investigate the clinical characteristics, treatment options, and prognosis of patients with gastric schwannoma (GS).

METHODS

Patients who were pathologically diagnosed with GS between April 2011 and October 2022 were enrolled. The data of clinical characteristics, pathological features, treatment options, and clinical outcomes were collected and compared between GS patients who underwent endoscopic resection (ER) and surgical resection (SR).

RESULTS

Of the 32 cases, 23 underwent SR and nine underwent ER. The median tumor size was significantly smaller in ER group than in SR group (12.0 vs. 40.0 mm, P < 0.001), while patients in SR group were older than those in ER group (54.5 ± 10.6 vs. 45.3 ± 10.9 years, P = 0.036). Moreover, tumors in ER group were more likely to exhibit an intraluminal pattern (100% vs. 26.1%, P < 0.001). Patients in ER group had significantly lower hospitalization cost (25859.2 ± 8623.9 vs. 44953.0 ± 13083.8 RMB, P = 0.011) than those in SR group. No differences were found between the two groups in terms of R0 resection rate, operative time, estimated blood loss, adverse events, and recurrence rate. All patients were followed up for 4-96 months (mean: 35 months; median: 23 months), during which no evidence of recurrence or metastasis was observed.

CONCLUSIONS

Both ER and SR are safe and effective treatment modalities for the management of GS, with ER being associated with lower medical costs compared to SR. The majority of GS are benign and do not recur, with little possibility of malignant transformation.

Laparoscopic resection for gastric schwannoma larger than 30 mm with long-term outcomes

BACKGROUND AND AIMS

Laparoscopic resection has been reported as effective and safe for gastric schwannoma (GS) in the form of case reports. However, study on laparoscopic surgery in patients with GS larger than 30 mm has been rarely reported. To this end, the present study aimed to evaluate the safety and efficacy of laparoscopic resection for the treatment of GS larger than 30 mm and its long-term outcomes.

METHODS

This is a retrospective case series study of patients with GS larger than 30 mm who underwent laparoscopic resection at our hospital between January 2014 and December 2020. Clinical pathology, surgical and follow-up data were collected and analyzed.

RESULTS

A total of 10 patients with a mean age of 51.6 years were included. Seven tumors were located in gastric body, 2 in antrum and 1 in fundus. Laparoscopic gastric wedge resection was performed in 7 patients, while laparoscopic gastric local resection was performed in 3 patients. All patients achieved complete resection. The mean operation time was 112.6 ± 34.3 min, and the mean postoperative hospital stay was 13.8 ± 5.1 days. Postoperative gastroplegia occurred in 2 patients and was treated with conservative therapy. No recurrence, metastasis or residue was found during the follow-up of mean 45.1 months.

CONCLUSIONS

Laparoscopic resection is a safe and effective method for treating GS larger than 30 mm with favorable long-term follow-up outcomes. Laparoscopic resection may be considered as the first-line treatment for GS larger than 30 mm.

Current Status of Endoscopic Full-Thickness Resection for Gastric Subepithelial Tumors: A Literature Review Over Two Decades

BACKGROUND

With the development of endoscopic technology and devices, endoscopic full-thickness resection (EFTR) has been challengingly introduced for gastric subepithelial tumors (SETs). The resection and closure strategies are under investigation. This systematic review was performed to assess the current status and limitations of EFTR for gastric SETs.

SUMMARY

MEDLINE was searched using the keywords "endoscopic full-thickness resection" or "gastric endoscopic full-thickness closure" AND "gastric" or "stomach" from January 2001 to July 2022. The outcome variables were the complete resection rate, major adverse event (AE) rate including delayed bleeding and delayed perforation, and closure-associated outcomes. Among 288 studies, 27 eligible studies involving 1,234 patients were included in this review. The complete resection rate was 99.7% (1,231/1,234). The major AE rate was 1.13% (14/1,234), with delayed bleeding in two (0.16%) patients, delayed perforation in one (0.08%), panperitonitis or abdominal abscess in three (0.24%), and other AEs in eight (0.64%). Surgical interventions were required intraoperatively or postoperatively in 7 patients (0.56%). Three patients underwent intraoperative conversion to surgery, due to intraoperative massive bleeding, technical difficulty of closure, and retrieval of falling tumor in the peritoneal cavity. Postoperative surgical rescues for AEs were required in four (0.32%). Subgroup analysis of AE outcomes showed no significant differences among closure techniques consisting of endoclips, purse-string suturing, and over-the-scope clips.

KEY MESSAGES

This systematic review demonstrated acceptable outcomes of EFTR and closure for gastric SETs, indicating that EFTR is a promising forthcoming procedure.

Schwannoma: A Rare Case of Submucosal Gastric Tumor

Schwannoma is a tumor that originates from the Schwann cells that surround a neuron's axon. This tumor is very rare in the gastrointestinal tract and develops submucosally from intestinal nerve plexuses. The most common location for gastrointestinal schwannomas is the stomach, where they account for only 0.2% of gastric tumors. We present the case of a 56-year-old asymptomatic patient who was diagnosed, following a routine ultrasound examination, with an abdominal tumor. An abdominal MRI confirmed the gastric origin of the tumor. Although a subsequent upper-digestive endoscopic ultrasound was performed, a definitive diagnosis could not be established. Thus, a laparoscopic wedge resection of the stomach was performed. The immunohistochemical examination of the tumor established the diagnosis of benign schwannoma. Despite the availability of advanced endoscopy and imaging techniques, the diagnosis of gastric schwannoma is very rarely preoperative. The immunohistochemical identification of S-100 on the surgical specimen confirmed the diagnosis.

The factors influencing the accuracy of pre-operative endoscopic ultrasonography assessment in endoscopic treatments for gastrointestinal tumors

BACKGROUND

This retrospective study aimed to evaluate the factors influencing the accuracy of Endoscopic Ultrasonography (EUS) as a preoperative assessment for gastrointestinal tumors.

METHODS

A total of 261 patients with 264 gastrointestinal tumors were enrolled in the study. The parameters of the gastrointestinal lesions examined under EUS and their pathology were recorded and analyzed.

RESULTS

The accuracy of EUS for detecting intramucosal lesions and subepithelial lesions (SELs) were 83.6% and 91.4%, respectively. One hundred and ninety-four (73.5%) lesions originated from the mucous layer, as determined by pre-operation EUS examinations. The accuracy of EUS in predicting the correct T stage for intramucosal lesions in the gastric region, esophagus, and colorectum was 77%, 71.8%, and 84.6%, respectively. According to the Paris endoscopic classification, the distribution of macroscopic patterns was different between the EUS-pathology conformity and nonconformity groups (p = 0.018). In the nonconformity group, 48.6% of erosive lesions were classified as 0-IIc, 0-IIa + IIc, 0-IIc + IIa or 0-III macroscopic patterns compared with 26% patients in the conformity group (p = 0.025). Univariate analyses demonstrated that ulcerative lesions (OR = 7.516, 95% Confidence Interval [CI] 2.574-21.952, p < 0.001), location at the cardia of the stomach (OR = 3.619, 95%CI 1.076-12.168, p = 0.038), malignant tumor (OR = 2.920, 95%CI 1.339-6.368, p = 0.007) were significantly associated with EUS inaccuracy. Multivariate logistic regression analyses showed that ulcer was an independent risk factor associated with EUS inaccuracy, with odds ratios of 5.094 (95% CI: 1.641-15.807, p = 0.005).

CONCLUSIONS

Our findings suggested that EUS is a reliable and easy-to-use diagnostic tool in decision-making regarding appropriate endoscopic treatment for gastrointestinal tumors. However, the diagnostic accuracy of EUS appeared questionable in the presence of ulceration.

Endoscopic ultrasonography is useful for predicting perforation in the endoscopic resection of gastric submucosal tumors originating from the muscularis propria: a retrospective case-control study

PURPOSE

Models for predicting perforation during endoscopic resection (ER) of gastric submucosal tumors (SMTs) originating from the muscularis propria (MP) are rare. Therefore, this study was conducted to determine important parameters in endoscopic ultrasonography (EUS) images to predict perforation and to build predictive models.

METHODS

Consecutive patients with gastric SMTs originating from the MP who received ER from May 1, 2013 to January 15, 2021 were retrospectively reviewed. They were classified into case and control groups based on the presence of perforation. Logistic multivariate analysis was used to identify potential variables and build predictive models (models 1 and 2: with and without information on tumor pathology, respectively).

RESULTS

In total, 199 EUS procedures (194 patients) were finally chosen, with 99 procedures in the case group and 100 in the control group. The ratio of the inner distance to the outer distance (I/O ratio) was significantly larger in the case group than in the control group (median ratio, 2.20 vs. 1.53; P<0.001). Multivariate analysis showed that age (odds ratio [OR], 1.036 in model 1; OR, 1.046 in model 2), the I/O ratio (OR, 2.731 in model 1; OR, 2.372 in model 2), and the pathology of the tumors (OR, 10.977 for gastrointestinal stromal tumors; OR, 15.051 for others in model 1) were risk factors for perforation. The two models to predict perforation had areas under the curve of 0.836 (model 1) and 0.755 (model 2).

CONCLUSION

EUS was useful in predicting perforation in ER for gastric SMTs originating from the MP. Two predictive models were developed.

Clinicopathological characteristics of gastrointestinal schwannomas: A retrospective analysis of 78 cases

Introduction

Schwannomas are tumors arising from Schwan cells of the neural sheath, which rarely occur in the gastrointestinal tract. The aim of the present study was to analyze the clinicopathological features and treatment outcomes of gastrointestinal schwannomas (GISs).

Methods

Patients who were diagnosed with GISs in our hospital from January 2010 to December 2021 were selected. Data about demographic characteristics, clinical symptoms, treatment methods and outcomes, pathological results, and follow-up results were retrospectively collected and analyzed.

Results

A total of 78 patients with 79 GISs were included, the female-to-male ratio was 55:23, and the average age was 52.12 ± 12.26 years. One-third (26/78) of the patients were asymptomatic. A total of 79 GISs were removed, and the average size was 3.63 ± 2.03 cm (range, 0.3-10 cm). As for tumor location, 54 GISs were located in the stomach, 14 in the esophagus, 2 in the duodenum, 6 in the colorectum (4 in the colon and 2 in the rectum), and the other 3 in the small intestine. A total of 23 and 55 patients underwent endoscopic and surgical resections, respectively. Compared with surgical resection, endoscopic resection is associated with a smaller diameter, lower cost, and shorter hospital stay. Pathological results revealed that S100 was positive in all the GISs. No recurrence was noticed during a median follow-up of 45 months (range, 6-148 months).

Conclusion

GISs are rare gastrointestinal tumors with favorable prognoses, which are most commonly seen in the stomach and diagnosed by pathological findings with immunohistochemical staining. Surgical resection remains the standard method for removing GISs, while endoscopic resection may serve as an alternative method for selected patients with GISs and may be attempted in GISs with a diameter of <3 cm and no signs of malignancy.

Laparoscopic-assisted endoscopic full-thickness resection of a large gastric schwannoma: A case report

BACKGROUND

Schwannomas, also known as neurinomas, are benign tumors derived from Schwann cells. Gastrointestinal schwannomas are rare and are most frequently reported in the stomach. They are usually asymptomatic and are difficult to diagnose preoperatively; however, endoscopy and imaging modalities can provide beneficial preliminary diagnostic data. There are various surgical options for management. Here, we present a case of a large gastric schwannoma (GS) managed by combined laparoscopic and endoscopic surgery.

CASE SUMMARY

A 28-year-old woman presented with a 2-mo history of epigastric discomfort and a feeling of abdominal fullness. On upper gastrointestinal endoscopy and endoscopic ultrasonography, a hypoechogenic submucosal mass was detected in the gastric antrum: It emerged from the muscularis propria and projected intraluminally. Computed tomography showed a nodular lesion (4 cm × 3.5 cm), which exhibited uniform enhancement, on the gastric antrum wall. Based on these findings, a preliminary diagnosis of gastrointestinal stromal tumor was established, with schwannoma as a differential. Considering the large tumor size, we planned to perform endoscopic resection and to convert to laparoscopic treatment, if necessary. Eventually, the patient underwent combined laparoscopic and gastroscopic surgery. Immunohistochemically, the resected specimen showed positivity for S-100 and negativity for desmin, DOG-1, α-smooth muscle actin, CD34, CD117, and p53. The Ki-67 index was 3%, and a final diagnosis of GS was established.

CONCLUSION

Combined laparoscopic and endoscopic surgery is a minimally invasive and effective treatment option for large GSs.

Endoscopic management of subepithelial lesions including neuroendocrine neoplasms: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends endoscopic ultrasonography (EUS) as the best tool to characterize subepithelial lesion (SEL) features (size, location, originating layer, echogenicity, shape), but EUS alone is not able to distinguish among all types of SEL.Strong recommendation, moderate quality evidence. 2: ESGE suggests providing tissue diagnosis for all SELs with features suggestive of gastrointestinal stromal tumor (GIST) if they are of size > 20 mm, or have high risk stigmata, or require surgical resection or oncological treatment.Weak recommendation, very low quality evidence. 3: ESGE recommends EUS-guided fine-needle biopsy (EUS-FNB) or mucosal incision-assisted biopsy (MIAB) equally for tissue diagnosis of SELs ≥ 20 mm in size.Strong recommendation, moderate quality evidence. 4: ESGE recommends against surveillance of asymptomatic gastrointestinal (GI) tract leiomyomas, lipomas, heterotopic pancreas, granular cell tumors, schwannomas, and glomus tumors, if the diagnosis is clear.Strong recommendation, moderate quality evidence. 5: ESGE suggests surveillance of asymptomatic esophageal and gastric SELs without definite diagnosis, with esophagogastroduodenoscopy (EGD) at 3-6 months, and then at 2-3-year intervals for lesions < 10 mm in size, and at 1-2-year intervals for lesions 10-20 mm in size. For asymptomatic SELs > 20 mm in size that are not resected, ESGE suggests surveillance with EGD plus EUS at 6 months and then at 6-12-month intervals.Weak recommendation, very low quality evidence. 6: ESGE recommends endoscopic resection for type 1 gastric neuroendocrine neoplasms (g-NENs) if they grow larger than 10 mm. The choice of resection technique should depend on size, depth of invasion, and location in the stomach.Strong recommendation, low quality evidence. 7: ESGE suggests considering removal of histologically proven gastric GISTs smaller than 20 mm as an alternative to surveillance. The decision to resect should be discussed in a multidisciplinary meeting. The choice of technique should depend on size, location, and local expertise.Weak recommendation, very low quality evidence. 8: ESGE suggests that, to avoid unnecessary follow-up, endoscopic resection is an option for gastric SELs smaller than 20 mm and of unknown histology after failure of attempts to obtain diagnosis.Weak recommendation, very low quality evidence. 9: ESGE recommends basing the surveillance strategy on the type and completeness of resection. After curative resection of benign SELs no follow-up is advised, except for type 1 gastric NEN for which surveillance at 1-2 years is advised.Strong recommendation, low quality evidence. 10: For lower or upper GI NEN with a positive or indeterminate margin at resection, ESGE recommends repeating endoscopy at 3-6 months and another attempt at endoscopic resection in the case of residual disease.Strong recommendation, low quality evidence.

Safety and Efficacy of Endoscopic Treatment of Solitary Gastric Neurofibroma

Purpose

The studies on solitary gastric neurofibroma (GN) consist of only individual case reports, with little data and relevant information. We aimed to summarize the clinical features, endoscopic features, imaging findings, and pathological features and study the safety and efficacy of endoscopic treatment of solitary GN.

Patients and Methods

We retrospectively collected and analyzed clinical data of patients who underwent endoscopic treatment in Department of Gastroenterology of a well-known tertiary hospital from August 2007 to September 2019 and were accurately diagnosed as having solitary GN.

Results

A total of 788 patients with gastric submucosal tumors underwent endoscopic treatment, among whom 11 patients were found to have solitary GNs. The incidence of solitary GNs was 1.4%. All 11 patients were treated with endoscopy. Five patients underwent endoscopic full-thickness resection (EFTR) and six patients underwent endoscopic submucosal excavation (ESE). The en bloc resection rate of the 11 lesions was 100.0%. The median endoscopic operation time was 80 minutes. Average length of hospital stay was 6.4 ± 1.6 days. The median follow-up time was 29 months. No recurrence, distant metastasis, or disease-related death occurred during the follow-up.

Conclusion

EFTR and ESE can serve as feasible, safe, and effective treatments for solitary GN.

Gastric schwannoma treated by endoscopic full-thickness resection and endoscopic purse-string suture: A case report

BACKGROUND

Schwannomas, also known as neurinomas, are tumors that derive from Schwann cells. Gastrointestinal schwannomas are extremely rare, but the stomach is the most common site. Gastric schwannomas are usually asymptomatic. Endoscopy and imaging modalities might offer useful preliminary diagnostic information. However, to diagnose schwannoma, the immunohistochemical positivity for S-100 protein is essential, whereas CD117, CD34, SMA, desmin, and DOG-1 are negative.

CASE SUMMARY

A 45-year-old female was found to have a gastric mass during a medical examination, which was diagnosed as a gastric schwannoma. We performed endoscopic full-thickness resection and endoscopic purse-string suture. Pathology and immunohistochemical staining confirmed the diagnosis of gastric schwannoma through the positivity of S-100 protein. Furthermore, to exclude the misdiagnosis of gastrointestinal stromal tumor, we performed a mutational detection of the c-Kit and PDGFRA genes. Postoperative follow-up revealed that the patient recovered well.

CONCLUSION

Immunohistochemical staining is essential for the diagnosis of schwannoma. Endoscopic full-thickness resection is an effective treatment method for gastric schwannoma.

Recent Progress and Challenges in the Diagnosis and Treatment of Gastrointestinal Stromal Tumors

Simple Summary

Gastrointestinal stromal tumors (GIST) are potentially malignant tumors and require evidence-based surgical and/or medical treatment. Laparoscopy has similar safety and prognostic outcomes to those of laparotomy and is currently a standard procedure for localized GISTs. However, surgery for gastric GISTs less than 2 cm may be re-evaluated due to the indolent nature of the GIST and other competing risks among GIST patients. A work-up with endoscopy and endoscopic ultrasonography as well as endoscopic or percutaneous biopsy is important for the preoperative diagnosis of GISTs. Medical treatment with tyrosine kinase inhibitors is the mainstay for recurrent/metastatic GISTs. The activity of an individual drug is well correlated with gene alterations, and, in the era of precision medicine, cancer genome profiling should be considered before medical treatment.

Abstract

Gastrointestinal stromal tumors (GISTs) are the most frequent malignant mesenchymal tumors in the gastrointestinal tract. The clinical incidence of GISTs is estimated 10/million/year; however, the true incidence is complicated by frequent findings of tiny GISTs, of which the natural history is unknown. The initial work-up with endoscopy and endoscopic ultrasonography plays important roles in the differential diagnosis of GISTs. Surgery is the only modality for the permanent cure of localized GISTs. In terms of safety and prognostic outcomes, laparoscopy is similar to laparotomy for GIST treatment, including tumors larger than 5 cm. GIST progression is driven by mutations in KIT or PDGFRA or by other rare gene alterations, all of which are mutually exclusive. Tyrosine kinase inhibitors (TKIs) are the standard therapy for metastatic/recurrent GISTs. Molecular alterations are the most reliable biomarkers for TKIs and for other drugs, such as NTRK inhibitors. The pathological and genetic diagnosis prior to treatment has been challenging; however, a newly developed endoscopic device may be useful for diagnosis. In the era of precision medicine, cancer genome profiling by targeted gene panel analysis may enable potential targeted therapy even for GISTs without KIT or PDGFRA mutations.

Impact of Body Mass Index (BMI) on perioperative outcomes following minimally invasive retromuscular abdominal wall reconstruction: a comparative analysis

BACKGROUND

Morbidity and recurrence rates are higher in obese patients undergoing open abdominal wall reconstruction (AWR). Historically, body mass index (BMI) ≥ 40 has served as a relative contraindication to open AWR. The purpose of this study is to evaluate the impact of minimally invasive surgery (MIS) on outcomes after AWR for higher versus lower BMI patients.

METHODS

A retrospective review of a prospectively maintained database was conducted of all patients who underwent MIS AWR between September 2015 and April 2019 at our institution. Patients were subdivided into two groups based on their BMI: BMI ≤ 35 kg/m² and BMI > 35 kg/m². Patient demographics and perioperative data were evaluated using univariate and multivariate analysis.

RESULTS

461 patients were identified and divided into two groups: BMI ≤ 35 (n = 310) and BMI > 35 (n = 151). The two groups were similar in age (BMI ≤ 35: 56.3 ± 14.1 years vs. BMI > 35: 54.4 ± 11.9, p = .154). BMI > 35 group had more patients with ASA score of 3 (81% vs. 32%, p < .001) and comorbid conditions such as hypertension (70% vs. 45%, p < .001), diabetes mellitus (32% vs. 15%, p < .001), and history of recurrent abdominal wall hernia (34% vs. 23%, p = .008). BMI > 35 group underwent a robotic approach at higher rates (74% vs. 45%, p < .001). Patients who underwent a Rives-Stoppa repair from the higher BMI cohort also had a larger defect size (5.6 ± 2.4 cm vs. 6.7 ± 2.4 cm, p = .004). However, there were no differences in defect size in patients who underwent a transversus abdominus release (BMI ≤ 35: 9.7 ± 4.9 cm vs. BMI > 35: 11.1 ± 4.6 cm, p = .069). Both groups benefited similarly from a short length of stay, similar hospital charges, and lower postoperative complications.

CONCLUSION

Initial findings of our data support the benefits of elective MIS approach to AWR for patients with higher BMI. These patients derive similar benefits, such as faster recovery with low recurrence rates, when compared to lower BMI patients, while avoiding preoperative hernia incarceration, postoperative wound complications, and hernia recurrences. Future follow-up is required to establish long-term perioperative and quality of life outcomes in this patient cohort.

Handheld robotic needle holder training: slower but better

BACKGROUND

Handheld robotic laparoscopic instruments fill the gap between robotic and conventional instruments, combining the advantages of degrees of freedom and low price. The difficulty and value in learning these new instruments require detailed investigation.

METHODS

Forty novice surgeons with no laparoscopic experience were randomly assigned to two groups: conventional instrument group (Group Conv) and robotic instrument group (Group Rob). The same training protocol was used in both groups: after viewing a standard operation film, laparoscopic suture training was administered using the corresponding instruments. After each training period, surgeons were tested using a force-sensing test platform. Maximum force (MF) and impulse (IMP) of operators through each ring were recorded. Learning curves based on MF and IMP for both instruments were compared. Institutional review board approval is not needed for this study.

RESULTS

MF and IMP of both groups decreased with increased training time; the learning curve of Group Conv decreased faster than that of Group Rob. When training time reached 13 h, the MF of Group Rob was significantly lower than that of Group Conv (P < 0.05), while IMP showed no significant difference between the two groups.

CONCLUSIONS

Effective training reduces operator MF and IMP, possibly decreasing damage to tissues with both conventional and handheld robotic needle holders. Group Rob took longer to reach a plateau, but subsequently had lower suture tension than did Group Conv. MF is more sensitive than IMP for measuring performance progress.