Self-expandable duodenal metal stent placement for the palliation of gastric outlet obstruction over the past 20 years

Efficacy of a higher-flexibility duodenal stent for palliation of gastric outlet obstruction

Background and study aims

Duodenal self-expandable metallic stent (SEMS) placement is a common palliative treatment for malignant gastric outlet obstruction symptoms (GOOS). The higher flexibility of the WallFlex Duodenal Soft stent aims to ease stent placement and reduce adverse events (AE). This descriptive study compared the WallFlex Soft stent with other duodenal SEMS designs with regard to efficacy and safety.

Patients and methods

Patients receiving the WallFlex Duodenal Soft stent as first-line treatment for GOOS were included in a prospective cohort (2019-2023). A retrospective cohort (1998-2019) with patients treated with other duodenal SEMS designs as first-line treatment for GOOS was used for comparison.

Results

In the prospective cohort, 11 patients were treated with the WallFlex Duodenal Soft, achieving 100% technical and 82% clinical success rates. The retrospective cohort of 147 patients with various types of duodenal SEMS showed 97% technical and 86% clinical success. For the WallFlex Duodenal Soft vs. the other duodenal SEMS, the overall survival was 101 vs. 82 days and median symptom-free survival was 83 vs. 28 days. AE rates were 18% vs. 28%, respectively.

Conclusions

The WallFlex Duodenal Soft stent effectively treats GOOS in palliative patients and seems to be associated with longer symptom-free survival and lower AE rates compared with previous duodenal SEMS designs.

Predictive factors for long-term patency in duodenal stenting for malignant gastric outlet obstruction

Background and study aims

Malignant gastric outlet obstruction (GOO) occurs often late during disseminated disease, requiring palliation. Placement of duodenal self-expandable metal stents (SEMS) is a common method for relieving malignant GOO but recurrent obstruction is common, warranting reintervention. The aim of the present study was to identify predictive factors for stent patency at 3 months and survival. Also, stent patency rate and adverse events after duodenal stenting were analyzed.

Patients and methods

This was a retrospective observational single-center study including all patients with malignant GOO receiving duodenal SEMS for palliation (2008-2021). Logistic regression for stent patency (3 months) and Cox regression for survival were undertaken.

Results

Overall, 198 patients were included. The most common malignancies were pancreatic adenocarcinoma (40%), gastric adenocarcinoma (18%), and cholangiocarcinoma (13%). Uncovered SEMS were used in 88% of patients and the reintervention rate was 44%. The stent patency rate was 63% in 188 patients with clinical success. Predictors of stent patency at 3 months were jaundice, semi- or fully-covered stents, and chemotherapy prior to stenting. Median survival was 81 days (interquartile range 40-241) after stenting. In Cox regression, predictors for overall survival at 6 months were absence of jaundice and stent patency at 3 months. Stent dysfunction was the most common cause of reintervention and was managed by repeated stent (76%) or dilation (11%).

Conclusions

Treatment of malignant GOO with duodenal SEMS is effective but the reintervention rate is high. Predictors of stent patency were jaundice, semi- or fully-covered SEMS, and chemotherapy. Survival was impaired by jaundice and stent dysfunction.

Treatment of choice for malignant gastric outlet obstruction: More than clearing the road

In this editorial, we comment on the in-press article in the World Journal of Gastrointestinal Endoscopy concerning the treatment of malignant gastric outlet obstruction (mGOO). The original theory of treatment involves bypassing the obstruction or reenabling the patency of the passage. Conventional surgical gastroenterostomy provides long-term relief of symptoms in selected patients, with substantial morbidity and a considerable rate of delayed gastric emptying. Endoscopic stenting was introduced as an alternative minimally invasive procedure with less procedural morbidity and rapid clinical improvement; however, it presented a high rate of long-term recurrence. Therefore, challenges remain in the treatment of mGOO patients to improve clinical outcomes. Endoscopic ultrasound-guided gastroenterostomy has recently emerged as a promising method because of the combined effects of surgery and endoscopy, whereas stomach-partitioning gastrojejunostomy has been reported as a modified surgical procedure to reduce the rate of delayed gastric emptying. In decision-making regarding the treatment of choice, it should be taken into account that mGOO might be accompanied by a variety of pathological conditions, including cancer cachexia, anorexia, malabsorption, and etc., all of which can also lead to the characteristic symptoms and poor nutritional status of mGOO. The treatment plan should consider comprehensive aspects of patients to achieve practical improvements in prognosis and the quality of life.

Propensity score-matched retrospective cohort study of endoscopic ultrasound-guided gastroenterostomy and enteral stenting for malignant gastric outlet

BACKGROUND

Symptomatic malignant gastric outlet obstruction (GOO) significantly reduce patients' quality of life. Endoscopic treatment involves enteral stenting or endoscopic ultrasonography to perform gastroenterostomy (EUS-GE). Aim was to compare enteral stenting with EUS-GE for endoscopic treatment of malignant GOO.

METHODS

We retrospectively compared enteral stenting with EUS-GE for the treatment of malignant GOO. Patients treated at our institution were identified and a propensity score matching analysis was performed. Treatment failure was the primary outcome, while the secondary endpoints were time until treatment failure, technical and clinical success rates, and adverse event rates.

RESULTS

Eighty-eight patients were included in the final analysis. Of whom, 44 were included in each of the two treatment groups. Treatment failure occurred significantly more frequently in the enteral stenting group (13/44) compared with the EUS-GE group (4/44; hazard ratio: 4,9; 95% CI 1.6-15.1). A Kaplan-Meier analysis revealed a median time until treatment failure of 22.0 weeks (95% CI 4.6-39.4) in the enteral stenting group compared with 76.0 weeks (95% CI 55.9-96.1) in the EUS-GE group (P = .002). No difference in technical success and clinical success was detected. Technical success was achieved in 43/44 patients (97.7%) in the enteral stenting group compared with 41/44 patients (93.2%) in the EUS-GE group, while clinical success was achieved in 32/44 (72.7%) and 35/44 (79.5%) patients, respectively. Nine adverse events were observed (9/44, 10.2%). There were no differences in 30-day adverse event rate and 30-day mortality rate.

CONCLUSION

EUS-GE was superior to enteral stenting in the treatment of malignant GOO in terms of treatment failure and time until treatment failure in a propensity score-matched cohort.

Incidence and factors associated with stent dysfunction and pancreatitis after gastroduodenal stenting for malignant gastric outlet obstruction

Background and study aims Endoscopic gastroduodenal stent (GDS) deployment is currently a standard treatment for malignant gastric outlet obstruction (mGOO) in patients with limited life expectancy; however, stent dysfunction (SD) and complicated pancreatitis often occur after GDS deployment. We investigated incidence and contributing factors of SD and complicated pancreatitis. Patients and methods We retrospectively reviewed 203 patients who underwent initial GDS deployment for palliation of mGOO symptoms between October 2017 and July 2022, including 109 who underwent GDS deployment across the duodenal papilla (sub-cohort). Results SDs, including tumor ingrowth (n = 26), kinking (n = 14), and migration (n = 13), occurred in 68 patients (33.5%). Cumulative SD incidence was 41.1% (95% confidence interval, 32.6-49.4%). SD incidence increased to 0.4%, 0.16%, and 0.06% per day at < 8, 8-16, and>16 weeks, respectively. On multivariate analysis, Niti-S pyloric/duodenal stent deployment (sub-distribution hazard ratio [sHR] 0.26, P = 0.01) and survival length ≥ 90 days (sHR 2.5, P = 0.01) were respectively identified as favorable and risk factors significantly associated with SD. Pancreatitis developed in 14 patients (12.8%) in the sub-cohort, which had significantly higher parenchymal diameter ( P < 0.01) and lower main pancreatic duct (MPD) caliber ( P < 0.01) than the non-pancreatitis cohort. On multivariate analysis, MPD caliber < 3 mm independently predicted pancreatitis (odds ratio 6.8, P = 0.03). Conclusions Deployment of the Niti-S pyloric/duodenal stent, with conformability even for angulated strictures, significantly reduced the incidence of SD. Stent selection, life expectancy, and MPD caliber should be taken into consideration during decision-making for GDS deployment for mGOO.

Endoscopic gastrointestinal bypass anastomosis using deformable self-assembled magnetic anastomosis rings (DSAMARs) in a pig model

BACKGROUND

To investigate the feasibility of a deformable self-assembled magnetic anastomosis ring (DSAMAR), designed and developed by us, for endoscopic gastrointestinal bypass anastomosis.

METHODS

Ten experimental pigs were used as model animals. The DSAMAR comprises 10 trapezoidal magnetic units, arranged in a straight line under the constraint of a guide wire. When the desired anastomosis site is reached under the guidance of an endoscope, the catheter pushes the magnetic unit along the guide wire. The linear DSAMAR can be assembled into a circular DSAMAR. Two DSAMARs were inserted, one at the end of the duodenum and the other into the stomach successively. They attracted each other and compressed the wall of the stomach and duodenum to establish gastrointestinal bypass anastomosis. The experimental pigs were euthanized 4 weeks after the operation, and the gastrointestinal bypass anastomosis specimens were obtained. The anastomosis formation was evaluated by the naked eye and histology.

RESULTS

Gastrointestinal bypass anastomosis with DSAMARs was successfully performed. The average operation time under an endoscope was 70.30 ± 19.05 min (range: 43-95 min). The DSAMARs were discharged through the anus 10-17 days after surgery. There were no complications such as gastrointestinal bleeding, perforation, anastomotic fistula, and gastrointestinal obstruction during and after the operation. Gastroscopy and gross specimen of the anastomosis showed a well-formed magnetic anastomosis. Histological observation showed good continuity of the serous membrane and the mucosa of magnetic anastomosis.

CONCLUSION

The DSAMAR is a safe and feasible device for fashioning gastrointestinal bypass anastomosis in this animal model.

How to successfully administer palliative treatment with a stent for malignant gastric outlet obstruction?

Although endoscopic stenting (ES) has been widely used as a less-invasive palliation method for malignant gastric outlet obstruction (GOO), recent reports have highlighted issues related to the procedure. For successful treatment, various aspects must be assessed before considering the practices. First, it is necessary to eliminate cases with contraindications such as coexistence of distal small-bowel obstruction or perforation. Other factors potentially related to clinical failure (i.e., peritoneal carcinomatosis) may require consideration but remain controversial. ES has better short-term outcomes than surgical gastrojejunostomy (GJ). GJ has recently been considered preferable in cases with longer life expectancy because of superior sustainability. Various types of stents are now commercially available, but their ideal structure and mechanical properties have not yet been clarified. Covered metal stent may reduce stent obstruction but is prone to increase stent migration, and its significance remains uncertain. Subsequent chemotherapy after stenting should be considered, as it is expected to prolong patient survival without increasing the risk of adverse events. Furthermore, it may be helpful in preventing tumor ingrowth. In cases with GOO combined with biliary obstruction, biliary intervention is often difficult. Recently, endoscopic ultrasound-guided biliary drainage (EUS-BD) has been widely used as an alternative procedure for endoscopic transpapillary biliary drainage (ETBD). Despite the lack of consensus as to whether ETBD or EUS-BD is preferred, EUS-BD is useful as a salvage technique for cases where ETBD is difficult. To perform stent placement successfully, it is important to pay attention to the above points; however, many remaining issues need to be clarified in the future.