Endoscopic Self-expandable Metal Stent Research Articles

Safety and Effectiveness of Colonic Stenting for Ileocecal Valve Obstruction and Usefulness of Two-Step Strategy: Single-Center Retrospective Study

Background: Endoscopic self-expandable metallic stent (SEMS) placement is a widely accepted treatment for malignant left-sided colorectal obstruction (LSO) because of its lower invasiveness and quicker symptomatic relief compared to surgery. However, SEMS placement for ileocecal valve obstruction (ICVO) has not been established due to its technical difficulties. Methods: This single-center retrospective study compared the clinical outcomes of patients who underwent SEMS placement for ICVO (ICVO group, n = 13) and LSO (LSO group, n = 146). Particularly in cases with severe small-intestine dilation, we applied a “Two-Step Strategy”, which involved long intestinal tube insertion followed by SEMS placement to ensure safety and overcome technical challenges. Results: Patients in the ICVO group were significantly more likely to undergo SEMS placement with the Two-Step Strategy compared to those in the LSO group (76.9% vs. 6.9%, p < 0.001). Both groups achieved similarly high technical and clinical success rates (100% vs. 98.6%, p = 1.000; 92.3% vs. 88.4%, p = 1.000), and the incidence of adverse events also showed no significant difference between the groups (7.7% vs. 13.0%; p = 1.000). Furthermore, the median time to recurrent colorectal obstruction and survival time after SEMS placement did not differ between patients with palliative stenting for ICVO and LSO (not reached vs. 430 days, p = 0.586; 119 days vs. 200 days, p = 0.303). Conclusions: SEMS placement for malignant ICVO is as safe and effective as it is for malignant LSO, and the Two-Step Strategy might be useful in ICVO cases.

Endoscopic self-expandable metal stent versus endoscopy vacuum therapy for traumatic esophageal perforations: a retrospective cohort study

BackgroundTraumatic esophageal perforations (TEP) are a grave medical condition and require immediate intervention. Techniques such as Esophageal Self-Expandable Metal Stent (E-SEMS) and Endoscopic Vacuum Therapy (EVT) show promise in reducing tissue damage and controlling esophageal leakage. The present study aims to compare the application of EVT to E-SEMS placement in TEP.MethodsRetrospective cohort study valuated 30 patients with TEP. The E-SEMS and EVT groups were assessed for time of hospitalization, treatment duration, costs, and clinical outcome.ResultsPatients treated with EVT (24.4 ± 13.2) demonstrated significantly shorter treatment duration (p < 0.005) compared to the group treated with E-SEMS (45.8 ± 12.9) and patients submitted to E-SEMS demonstrated a significant reduction (p = 0.02) in the time of hospitalization compared to the EVT (34 ± 2 vs 82 ± 5 days). Both groups demonstrated a satisfactory discharge rate (E-SEMS 93.7% vs EVT 71.4%) but did not show statistically significant difference (p = 0.3155). E-SEMS treatment had a lower mean cost than EVT (p < 0.05). Descriptive statistics were utilized, arranged in table form, where frequencies, percentages, mean, median, and standard deviation of the study variables were calculated and counted. The Fisher's Exact Test was used to evaluate the relationship between two categorical variables. To evaluate differences between means and central points, the parametric t-test was utilized. Comparisons with p value up to 0.05 were considered significant.ConclusionE-SEMS showed a shorter time of hospitalization, but a longer duration of treatment compared to EVT. The placement of E-SEMS and EVT had the same clinical outcome. Treatment with E-SEMS had a lower cost compared with EVT.

Efficacy and Safety Analysis of Emergency Endoscopic Self-Expanding Metal Stent Placement Without Fluoroscopic Assistance for Right-Sided Colonic Cancer Obstruction.

Traditionally, surgical treatment is recommended for right-sided colonic cancer obstruction (RCCO); however, the literature comparing surgical or non-surgical procedures is lacking. Patients included in this study were divided into two groups: one group received elective surgery after self-expanding metal stent (SEMS) placement, i.e., the bridge to surgery (BTS) group, and one group received emergency surgery (ES). Thirty-five patients were included in the BTS group and 60 patients underwent ES. The technical and clinical success rates for SEMS placement were 100% and 88.6%, respectively, while the short-term complication rates were 51.4% and 33.3% for the BTS and ES groups, respectively (p=0.082). Overall, 2.9% and 3.3% of postoperative deaths occurred in the BTS and ES groups (p=1.000). The 1-year overall survival (OS) rates were 91.4% and 88.3% (p=0.840), 3-year OS rates were 85.7% and 81.7% (p=0.860), and 5-year OS rates were 82.9% and 76.7% (p=0.620) in the BTS and ES groups, respectively. No tumor recurrence was found in the BTS group but seven recurrences were found in the ES group (11.7%) [p=0.091]. Laparoscopic surgery was chosen by 42.9% of patients in the BTS group and 26.7% of patients in the ES group (p=0.104); however, the length of hospital stay (p=0.001) was longer in the BTS group. In the two groups, no differences were found in terms of postoperative complications and mortality as well as OS. The BTS group preferred to perform laparoscopic surgery and the technical success rate of stenting was high, therefore SEMS for RCCO was considered safe and feasible.

Second Covered and Uncovered Self-Expandable Metal Stents for Recurrent Gastric Outlet Obstruction: A Retrospective Comparative Study.

Background: Endoscopic self-expandable metal stent (SEMS) placement is a current mainstay for malignant gastric outlet obstruction (GOO), but symptomatic recurrence due to initial SEMS dysfunction commonly occurs. We aimed to compare the safety and effectiveness of second SEMS for recurrent GOO (RGOO). Methods: Between April 2006 and December 2022, a total of 95 cases with malignant RGOO undergoing second endoscopic SEMS placement were enrolled. Technical and clinical success rates, RGOO, time to RGOO (TRGOO), stent patency rate, adverse events (AE), and overall survival (OS) were retrospectively compared between covered and uncovered SEMS (cSEMS/uSEMS) groups. Risk factors for TRGOO were also explored. Results: Baseline characteristics were well balanced between cSEMS (n = 48) and uSEMS (n = 47) groups, except for the causes of the initial SEMS dysfunction. High technical and clinical success rates with a similar incidence of AE (15% vs. 17%, p = 0.78) and OS (median of 101 vs. 102 days, p = 0.68) were achieved in both groups. There were no statistical differences in cumulative incidence of RGOO (19% vs. 13%, p = 0.58), TRGOO (median, not reached in both groups, p = 0.57), and stent patency rates at 1, 2, and 3 months between the groups (60%, 47% and 26%, respectively vs. 70%, 55% and 38%, respectively). However, TRGOO tended to be longer in cSEMS in cases with RGOO due to tumor ingrowth (median, not reached vs. 111 days, p = 0.19). A Cox regression analysis demonstrated that chemotherapy after second SEMS placement was significantly associated with an improved TRGOO (the hazard ratio of 0.27 [95% confidence interval, 0.08-0.93], p = 0.03). Conclusions: Regardless of the type of SEMS, second SEMS placement was similarly safe and effective for RGOO. The type of second SEMS might be considered based on the cause of initial SEMS dysfunction.

A novel fully covered metal stent for unresectable malignant distal biliary obstruction: results of a multicenter prospective study.

Endoscopic self-expandable metal stent (SEMS) placement is currently the standard technique for treating unresectable malignant distal biliary obstructions (MDBO). Therefore, covered SEMS with longer stent patency and fewer migrations are required. This study aimed to assess the clinical performance of a novel, fully covered SEMS for unresectable MDBO. This was a multicenter single-arm prospective study. The primary outcome was a non-obstruction rate at 6 months. The secondary outcomes were overall survival (OS), recurrent biliary obstruction (RBO), time to RBO (TRBO), technical and clinical success, and adverse events. A total of 73 patients were enrolled in this study. The non-obstruction rate at 6 months was 61%. The median OS and TRBO were 233 and 216 days, respectively. The technical and clinical success rates were 100% and 97%, respectively. Furthermore, the rate of occurrence of RBO and adverse events was 49% and 21%, respectively. The length of bile duct stenosis (<2.2 cm) was the only significant risk factor for stent migration. The non-obstruction rate of a novel fully covered SEMS for MDBO is comparable to that reported earlier but shorter than expected. Short bile duct stenosis is a significant risk factor for stent migration.

Treatment approach in malignant left-bowel obstruction using self-expandable metallic stent: a case series.

Endoscopic self-expandable metallic stent (SEMS) decompression in patients with bowel obstruction due to colon carcinoma has been practiced for over two decades now, both in potentially curable cases and metastatic cancer. Using this case series, we aim to review the literature on the subject and to present our initial experience with using this technique as a bridge to single stage surgery, thus minimizing colostomy creation.

Unilateral versus bilateral Y-type stent-in-stent metal stent insertions in inoperable malignant hilar biliary strictures: A multicenter retrospective study

BackgroundTo date, there is controversy regarding unilateral versus bilateral stent placement in patients with malignant hilar biliary strictures (MHBSs). The aim of this study was to compare the clinical outcomes and complications of unilateral and bilateral (stent-in-stent method) stent placements for these patients. MethodsWe conducted a multicenter retrospective analysis of patients with inoperable MHBS who underwent endoscopic self-expandable metal stent (SEMS) placement from January 2009 to December 2019. Two groups classified according to the stent procedure method were compared for demographic, procedural, and postprocedure factors. Survival analysis for patency loss and overall survival was also conducted. ResultsA total of 236 subjects were included. A superior technical success rate was found in the unilateral stent group (98.8% vs. 82.5%, P < 0.001), whereas the clinical success rate was higher in the bilateral group (85.7% vs. 70.5%, P = 0.028). There was no significant difference with respect to complications or patency loss, and the bilateral group had better overall survival (P < 0.01). In the Cox proportional hazard model, MHBSs from lymph node compression were associated with a higher risk of death (HR = 9.803, P = 0.003). In contrast, bilateral SEMS insertion showed reduced postprocedural mortality (HR = 0.316, P = 0.001). ConclusionsY-type stent-in-stent bilateral SEMSs are technically difficult but demonstrated more favorable overall survival for palliative bile drainage of inoperable MHBS patients compared to unilateral insertions.

Bridge to surgery using a self-expandable metallic stent for stages II\u2013III obstructive colorectal cancer

BackgroundBridge to surgery (BTS) using a self-expandable metallic stent (SEMS) for the treatment of obstructive colorectal cancer improves the patient’s quality of life. This study aimed to examine prognostic factors of obstructive colorectal cancer.MethodsWe analyzed stage II-III resectable colon cancer cases (Cur A) retrospectively registered between January 2005 and December 2017. Overall, 117 patients with Cur A obstructive colorectal cancer were evaluated: 67 of them underwent emergency surgery (ES Group) and 50 of them after BTS with SEMS placement (BTS group). We compared surgical results and prognoses between the two groups.ResultsA total of 50 patients underwent endoscopic SEMS placement, which technical success of 96% and morbidity rate of 18%. Primary anastomosis rates were 77.6% in ES and 95.7% in BTS (p < 0.001); postoperative complication, 46.3% in ES and 10.5% in BTS (p < 0.001); pathological findings of lymphatic invasion, 66.7% in ES and 100% in BTS (p < 0.001); venous invasion were 66.8% in ES and 92% in BTS (p = 0.04); and recurrence of 25.4% in ES and 39.1% in BTS. The 3-year overall survival was significantly different between two groups (ES, 86.8%:BTS, 58.8%), BTS is worse than ES (log-rank test; p < 0.001). Venous invasion independently predicted worsened recurrence-free and overall survival.ConclusionsThe vascular invasiveness was correlated with tumor progression after SEMS placement, and the survival rate was lower in BTS. SEMS potentially worsens prognostic outcomes in stage II–III obstructive colorectal cancer.

Comprehensive literature review of randomized clinical trials examining novel treatment advances in patients with colon cancer.

The treatment of colon cancer has had numerous recent advances, in terms of surgical approach, adjuvant therapies, and more. In this review, the authors examine randomized clinical trials comparing open surgery to laparoscopic surgery (including total mesocolic excision), and also examine the role of robotic surgery. Novel surgical techniques including the no-touch technique, side-to-side anastomosis, suture technique, complete mesocolic excision (CME) with central vascular ligation (CVL), and natural orifice transluminal endoscopic surgery (NOTES) are outlined. The role of placing endoscopic self-expandable metal stents (SEMS) for colonic obstruction is compared and contrasted with the surgical approach, and the effect that the anti-VEGF inhibitor bevacizumab may have on this side effect profile is further explored. The role of the resection of the primary tumor in the setting of metastatic disease is examined with respect to survival benefit. Pathways of perioperative care which can accelerate post-surgical recovery, including enhanced recovery after surgery (ERAS) are examined. The role of adjuvant chemotherapy in patients with high-risk stage II and patients with stage III disease is examined, along with the role on circulating tumor DNA (ctDNA) as well as with the biologic targeted agents cetuximab and bevacizumab. Lastly, the authors detail the postoperative surveillance schedules after surgical resection with respect to survival outcomes.

Novel Predictive Nomogram for Identifying Difficult Guidewire Insertion in Patients With Malignant Colorectal Obstruction and Sphincterotome-Assisted Guidewire Insertion for Improving the Success Rate of Self-Expandable Metal Stent Insertion.

Aims: This study aimed to identify risk factors related to guidewire insertion (GWI) failure and construct a novel predictive nomogram. In addition, sphincterotome-assisted guidewire insertion (SAGWI) in difficult cases was evaluated for efficacy and safety.Methods: We reviewed the data of 509 patients with malignant colorectal obstruction who underwent endoscopic self-expandable metal stent (SEMS) insertion from 2007 to 2018 in our center, retrospectively. We identify risk factors associated with GWI failure by multivariate logistic regression analysis and construct a novel predictive nomogram. Improvements in the GWI and technical and clinical success rates were assessed for the SAGWI technique.Results: A total of 509 patients with malignant colorectal obstruction were included. Increases of 6.9% and 7.0% were found in the GWI success rate by intention-to-treat (ITT; p < 0.001) and per-protocol (PP; p < 0.001) analyses after SAGWI, respectively. Increases of 6.5% and 6.6% in the technical success rate were found by ITT (p < 0.001) and PP (p < 0.001) analyses after SAGWI, respectively. Increases of 5.8% and 6.0% in the clinical success rate were found by ITT (p < 0.001) and PP (p < 0.001) analyses after SAGWI, respectively. Regarding the GWI failure-related factors, a sharply angulated stricture was an independent risk factor, and an experienced colonoscopist was an independent protective factor. A novel effective predictive nomogram was constructed.Conclusion: The novel predictive nomogram can be conveniently used to identify difficult cases. A sharply angulated stricture and an experienced colonoscopist are independent factors related to GWI failure. The SAGWI technique is an effective and safe method for addressing technically difficult cases.

Newly developed self-expandable Niti-S MD colonic metal stent for malignant colonic obstruction.

Colonic stents are increasingly used to treat acute malignant colonic obstructions. The WallFlex and Niti-S D type stents are the commonly used self-expandable metallic stents available in Japan since 2012. WallFlex stent has a risk of stent-related perforation because of its axial force, while the Niti-S D type stent has a risk of obstructive colitis because of its weaker radial force. Niti-S MD type stents not only overcome these limitations but also permit delivery through highly flexible-tipped smaller-caliber colonoscopes. To compare the efficacy and safety of the newly developed Niti-S MD type colonic stents. This single-center retrospective observational study included 110 patients with endoscopic self-expandable metallic stents placed between November 2011 and December 2018: WallFlex (Group W, n = 37), Niti-S D type (Group N, n = 53), and Niti-S MD type (Group MD, n = 20). The primary outcome was clinical success, defined as a resolution of obstructive colonic symptoms, confirmed by clinical and radiological assessment within 48 h. The secondary outcome was technical success, defined as accurate stent placement with adequate stricture coverage on the first attempt without complications. The technical success rate was 100% in Groups W, N, and MD, and the overall clinical success rate was 89.2% (33/37), 96.2% (51/53), and 100% (20/20) in Groups W, N, and MD, respectively. Early adverse events included pain (3/37, 8.1%), poor expansion (1/37, 2.7%), and fever (1/37, 2.6%) in Group W and perforation due to obstructive colitis (2/53, 3.8%) in Group N (likely due to poor expansion). Late adverse events (after 7 d) included stent-related perforations (4/36, 11.1%) and stent occlusion (1/36, 2.8%) in Group W and stent occlusion (2/51, 3.9%) in Group N. The stent-related perforation rate in Group W was significantly higher than that in Group N (P < 0.05). No adverse event was observed in Group MD. In our early and limited experience, the newly developed Niti-S MD type colonic stent was effective and safe for treating acute malignant colonic obstruction.

Colon metal stents as a bridge to surgery had no significant effects on the perineural invasion: a retrospective study

PurposeThe long-term oncological effects of self-expandable metallic stent (SEMS) as a “bridge to surgery” are contradictory, and perineural invasion was supposed to be enhanced by the stenting. In this retrospective study, we compared the perineural invasion and the oncological outcomes between the stent as a bridge to surgery (SBTS)- and emergency surgery (ES)-treated patients to evaluate the results of stenting on the perineural invasion.MethodsThe clinical data of patients with acute intestinal obstruction caused by colorectal cancer from January 2013 to January 2017 were retrospectively collected. Forty-three patients underwent semi-elective curative resection after endoscopic SEMS insertion, and sixty-three underwent ES. The adverse events and long-term follow-up outcomes were assessed. The clinicopathological characteristics, perineural invasion rates, and survival rates were compared between the two patient groups.ResultsStent insertion resulted in significantly lower stoma rate (32.6% vs 46%; P = 0.03), post-operative overall complication rate (11.6% vs 28.6%, P = 0.038), and total hospital stay (17.07 ± 5.544 days vs 20.48 ± 7.372 days, P = 0.042). Compared with the ES group, there was no significant increase in the incidence of peripheral invasion in the SBTS group (39.5% vs 47.6%, P = 0.411). No significant difference was noted in the survival rate and long-term prognosis between the SEMS and ES groups (P = 0.964). The technical success rate was 95.6%, and the clinical success rate was 97.7%.ConclusionsPreoperative colon stenting was an effective transitional method for colorectal cancer patients with complete obstruction. Short-term stent implantation had no significant effect on perineural invasion in patients with CRC.

Endoscopic Self-Expandable Metallic Stent Insertion without Fluoroscopic Guidance Is Feasible and Safe for Acute Colonic Obstruction Caused by Colorectal Cancer.

Aims Endoscopic self-expandable metallic stent (SEMS) insertion for acute colonic obstruction caused by colorectal cancer (CRC) is always performed under fluoroscopic guidance. This study evaluated the feasibility and safety of an endoscopic stenting procedure without fluoroscopic guidance. Methods A total of 36 patients with an acute colonic obstruction caused by CRC underwent endoscopic SEMS insertion using a colonoscope without fluoroscopic guidance, followed by analyses of the technical and clinical success and short-term complications. Results Total technical success rate and clinical success rate were 91.7% and 86.1%, respectively. The mean procedure time was 21.2 ± 10.3 minutes. There was no stent dislodgement. One case of hematochezia and two cases of tenesmus occurred in patients with left-sided complete obstructions. No other short-term complications occurred. Procedure time, technical success, and clinical success rate were 16.3 ± 9.4 minutes, 93.1%, and 89.6% for left-sided obstructions, respectively, and were 26.8 ± 10.7 minutes, 85.7%, and 71.4% for right-sided obstructions, respectively. For complete obstructions, procedure time, technical success, and clinical success rate were 22.5 ± 8.9 minutes, 90%, and 83.3%, respectively. In the incomplete cases, procedure time, technical success, and clinical success were 13.5 ± 6.7 minutes, 100%, and 100%, respectively. Technical success, clinical success, and short-term complications were not differed between lesion locations and degrees. Conclusions This simple technique is feasible and safe for palliation of acute colonic obstruction caused by CRC.

Clinical outcomes of iatrogenic upper gastrointestinal endoscopic perforation: a 10-year study

BackgroundUpper gastrointestinal endoscopic examination is a relatively safe procedure; however, all endoscopic procedures are invasive and are associated with a risk of iatrogenic perforation. To evaluate clinical outcomes of iatrogenic upper gastrointestinal endoscopic perforation. Factors associated with surgical management or mortality were analyzed.MethodsBetween November 2008 and November 2018, the medical records of 149,792 upper gastrointestinal endoscopic procedures were evaluated. The mechanisms of perforations were categorized as electrocoagulation-induced or blunt trauma-induced injuries. The incidence and clinical outcomes of iatrogenic perforations based on the types of procedures performed were evaluated.ResultsIatrogenic endoscopic perforations occurred in 28 cases (0.019%). Iatrogenic perforation-related mortality occurred in 3 patients. The iatrogenic perforation rate based on the types of procedures performed was as follows: diagnostic endoscopy = 0.002%, duodenal endoscopic mucosal resection = 0.9%, esophageal endoscopic submucosal dissection = 10.7%, gastric endoscopic submucosal dissection = 0.2%, endoscopic self-expandable metal stent insertion for malignant esophageal obstruction = 0.1%, duodenoscope-induced injury = 0.02%, endoscopic sphincterotomy = 0.08%, and ampullectomy = 6.8%. All electrocoagulation-induced perforations (n = 21) were managed successfully (15 cases of endoscopic closure, 5 cases treated conservatively, and 1 case treated surgically). Three patients died among those with blunt trauma-induced perforations (n = 7). The factors associated with surgical management or mortality were old age, poor performance status (Eastern Cooperative Oncology Group score ≥ 1), advanced malignancy, and blunt trauma.ConclusionsMost cases of electrocoagulation-induced iatrogenic perforations can be treated using endoscopic clips. If endoscopic closure fails for blunt trauma-induced perforations, prompt surgical management is mandatory.

Laparoscopic Approach to Large Bowel Neoplastic Obstruction After Self-Expandable-Metal-Stent (SEMS) Placement.

Endoscopic self-expandable metal stent (SEMS) placement as a bridge to surgery in large bowel neoplastic obstruction is an alternative to emergency surgery for the obstructive colorectal neoplasms. This study aims to analyze postoperative and long-term outcomes in a series of patients who underwent laparoscopic colorectal resection after SEMS placement. The analysis, after the stratification based on the time elapsed between the onset of the occlusive symptoms and the SEMS positioning, revealed an interesting result, with lower mortality for patients who underwent the procedure within 24 hours of hospitalization (P=0.0159). This trend may indicate the need to reduce the endoscopic time schedules as much as possible, even if an emergency procedure is needed. The laparoscopic approach, after stent placement as bridge therapy, can be a safe alternative to emergency surgery, if the procedure is precociously applied.

The efficacy of endoscopic stenting combined with laparoscopy in the treatment of left colon cancer with obstruction.

Endoscopic self-expandable metal stents (SEMSs) are the bridge of obstructive colorectal cancer surgery. The debate is still open on whether the procedure and effects can be the same between the SEMS combined obstructive colon cancer resection and nonobstructive colon cancer resection, both of which were under laparoscopic. This retrospective study was designed to compare whether the same effects could be achieved in both resections. The retrospective analysis was from September 2016 to November 2017. In the observation group (OG), 20 patients hospitalized for obstruction of the left colon cancer were included, who received obstructive colon cancer laparoscopic resection (LR) combined with SEMS insertion. In control group (CG), 20 patients were randomly selected, who underwent nonobstructive colon cancer LR during this period. The differences between the two groups were compared, including operation time, intraoperative blood loss, the number of removed lymph nodes, postoperative anal exhaust time, and hospital stay. Both groups were comparable in the age, gender, weight, the distribution of tumor, lymph node metastasis, tumor, node, and metastasis staging, operation time, intraoperative blood loss, the number of removed lymph nodes, and postoperative anal exhaust time. The hospital stay was 15.2 ± 1.3 days and 14.2 ± 1.5 days in OG and CG, respectively, and it was longer in OG than that of in CG (P = 0.032). Obstructive colon cancer LR combined with SEMS insertion was a safe and feasible radical treatment strategy. The same level of procedure and effects could be achieved, compared to that of nonobstructive colon cancer LR.

Clinical Feasibility and Safety of Endoscopic Self-Expandable Metal Stent Placement for Upper Gastrointestinal Pathologies

We aimed to review our experiences to evaluate the practicality, safety, and effectiveness of endoscopic stent placement for the palliation of malignant obstructions of the upper gastrointestinal system (GIS) and the treatment of postoperative complications such as failure of anastomoses and fistulae. Endoscopic stent placement is increasingly used in the upper GIS for the management of both high grade malignancies causing obstruction and benign pathologies such as anastomosis failures, gastrointestinal fistulae, and strictures. Hospital records, clinical data, and endoscopy reports of 61 patients who had undergone endoscopic stenting between the years 2012 and 2015 were analyzed retrospectively. For all patients, self-expandable metal covered stents were used. Data involving technical and clinical success rates, complication, morbidity, and mortality rates of the endoscopic stenting procedure was collected and simple statistical analyses were made. Endoscopic stenting was successful in 60 of 61 patients (98.3%). Overall technical success rate was found to be 98.3%; clinical success rate, 86.6%; complication rate, 4.9%. No stent related mortality was observed in our series. Endoscopic stents can be effectively and safely used in the treatment of various lesions of the upper GIS.

Gastric outlet obstruction caused by metastatic tumor of the stomach originating from primary breast cancer: A case report.

The most common sites of breast cancer metastasis are the bone, liver, lung and brain, while gastrointestinal metastasis from breast cancer is rare. We herein present the case of a 68-year-old woman who was admitted to our department with nausea and appetite loss. The patient's medical history included right mastectomy with sentinel lymph node biopsy 5 years earlier for invasive lobular carcinoma, measuring 6.2 cm in greatest diameter, without lymphovascular invasion. Two years after the surgery, the patient developed brain metastasis and underwent metastasectomy to control the neurological symptoms, including unsteadiness and asthenia. After the second surgery, the patient received systemic chemotherapy using S-1, followed by bevacizumab plus paclitaxel. However, due to bevacizumab-related cardiotoxicity, the treatment was switched to eribulin. On esophagogastroduodenoscopy, an elevated lesion was identified in the antrum, causing severe narrowing of the gastric outlet. Biopsy and histological examination of the tumor revealed infiltration of the gastric wall by undifferentiated neoplastic cells with poor adhesion, morphologically similar to invasive lobular carcinoma, and immunohistochemical staining was positive for estrogen receptor, mammaglobin and GATA3. Finally, 18F-2-deoxy-2-fluoro-D-glucose (FDG) positron emission tomography combined with computed tomography imaging revealed FDG uptake across the thickness of the antral wall. The patient was diagnosed with gastric metastasis from the original breast cancer and subsequently underwent endoscopic self-expandable metallic stent (SEMS) placement. There were no procedure-related adverse events, and the patient remained alive under best supportive care 4 months after SEMS placement. To the best of our knowledge, this is the first reported case of gastric outlet obstruction caused by metastatic breast carcinoma managed by SEMS placement. While such a diagnosis is rare, clinicians treating patients with gastric metastases should be aware of possible gastric outlet obstruction and SEMS placement as an effective palliative intervention.

Mo1714 COMPARISON OF FLARE TYPE COVERED SELF-EXPANDABLE METAL STENT WITH DOUBLE-LAYERED COVERED STENT FOR MALIGNANT COLORECTAL OBSTRUCTION

Endoscopic self-expandable metal stent (SEMS) placement has been used as an alternative or bridge to surgery for malignant colorectal obstruction. Covered SEMS is allegedly associated with high risk of migration. In an effort to reduce this risk, various new type stents have been developed. However, comparative outcomes of these stents have not been fully evaluated. We aimed to compare the efficacy and complication rates between flare covered stent (Flare) and double-layered covered stent (COMVI). We performed a prospective, randomized, open-label study from 4 tertiary referral centers in Korea. Between July 2016 and August 2017, patients with malignant colorectal obstruction were eligible for the study. Flare has a wider opening in the proximal end of stent whereas COMVI has an outer uncovered membrane in the center of stent to avoid migration. Primary outcome measure was migration rate within 1 month. Rates of technical success, clinical success and complications for 1 month such as perforation were also assessed. A total of 55 patients were included. Flare type stents were applied to 26 patients and 29 patients were received COMVI type stents (median age 73.0 [63.0-81.0], male 43.6%). The technical and clinical success rates of Flare and COMVI stent were 88.5% vs. 96.6% (p=0.526) and 88.5% vs. 82.1% (p=0.787), respectively. Although migration rate of COMVI for 1 month seemed to be higher than flare type, there was no statistical significance (17.9% vs. 7.7%, p=0.48). Median migration days after stent insertion of Flare and COMVI were 11.5 ± 9.2 and 10.4 ± 11.8, respectively (p=0.912). Overall complications including perforation andmigration for 1 month suggested no significant difference between Flare and COMVI stent (15.4% vs. 28.6%, p=0.403). Our study presents that both Flare and COMVI type stents are equally effective modalities for treating malignant colorectal obstruction, having similarity in clinical outcomes and complication rates. Stent migration appeared to be lower in Flare than COMVI type.

Fluoroscopic Gastroduodenal Stent Placement in 55 Patients with Endoscopic Stent Placement Failure.

To evaluate the technical feasibility and clinical effectiveness of fluoroscopic self-expandable metal stent (SEMS) placement in malignant gastroduodenal obstructions after failed endoscopic SEMS placement. Between September 2010 and July 2017, 874 patients underwent endoscopic SEMS placement for dysphagia caused by malignant gastroduodenal obstructions. Endoscopic SEMS placement failed in 55 of 874 patients (6.3%). These patients were referred for fluoroscopic SEMS placement. In case of failed fluoroscopic SEMS placement, combined endoscopic and fluoroscopic SEMS placement was attempted at the same setting. Fluoroscopic SEMS placement was technically successful in 40 of 55 patients (72.7%). Combined endoscopic and fluoroscopic SEMS placement was technically successful in 6 of 15 patients with fluoroscopic SEMS placement failure. Failures in the nine patients were due to complete obstruction (n = 5) and acute angulation at the stricture site (n = 4). The overall technical success rate was 83.6% (46/55). Clinical success was achieved in 95.6% of patients (44/46). Complications occurred in 7 of 46 patients (15.2%), including tumor overgrowth (n = 3), SEMS migration (n = 3), and bleeding (n = 1). The median SEMS patency and patient survival periods were 515 (95% confidence interval (CI), 266.6-761.5) and 83 (95% CI 60.6-105.4) days, respectively. Fluoroscopic SEMS placement is technically feasible and clinically effective in cases of endoscopic SEMS placement failure. A combined endoscopic and fluoroscopic approach increases the technical success rate after failure of the endoscopic or fluoroscopic approach. Level IV.