Efficacy and safety of uncovered self-expandable metal stents for distal malignant biliary obstruction in unresectable non-pancreatic cancer.

Objectives: The efficacy of uncovered self-expandable metal stents (UCSEMS) versus fully covered self-expandable metal stents for distal malignant biliary obstruction remains controversial. Additionally, the heterogeneity of the disease conditions has been indicated in previous studies because pancreatic and non-pancreatic cancers have different characteristics in clinical course. Therefore, the etiology of biliary obstruction necessitates investigations stratified by primary disease. This study aimed to evaluate the outcomes of UCSEMS, specifically for non-pancreatic cancer-induced distal malignant biliary obstruction. Methods: We conducted a single-center retrospective review to evaluate the time to recurrent biliary obstruction and frequency of adverse events (AEs) in patients receiving UCSEMS for unresectable non-pancreatic cancer-induced malignant biliary obstruction. Results: Overall, 32 patients were enrolled in the study between January 2016 and December 2023. The median time to recurrent biliary obstruction was 140 days. AE rates were low at 3.1% for both pancreatitis and cholecystitis, suggesting a potential benefit of UCSEMS in reducing post-procedural AEs. Conclusion: UCSEMS may reduce the risk of post-procedural AEs and should be considered in patients at high risk of post-endoscopic retrograde cholangiopancreatography pancreatitis. However, the patency period may be shorter, necessitating future comparative research with fully covered self-expandable metal stents to determine the optimal stent choice.

A New Self-Expandable Metallic Stent with Low Axial Force and a High Axial Force Zero-Border Shows a Very Low Perforation Rate in Malignant Colorectal Obstruction: A Japanese Multicenter Prospective Study.

Background: Recently, there has been a significant increase in the utilization of self-expandable metallic stents (SEMSs) for treating malignant colorectal obstructions through colorectal stenting. The mechanical properties of SEMSs are usually considered to affect clinical outcomes of patients with malignant colorectal obstructions. Methods: This single-arm, prospective, multicenter study of SEMS with a lower axial force and high axial force zero-border included 200 patients with malignant colorectal obstruction. Technical and clinical success, stent patency, and adverse events associated with SEMS placement were evaluated. Results: One patient was excluded, and 199 patients were evaluated. The treatment intent was bridge-to-surgery in 129 and palliation in 70 patients. Technical and clinical success rates were 99.5% and 97.0%, respectively. The percentage of the ColoRectal Obstruction Scoring System scores of 3 or higher improved significantly from 19.2% before placement to 93.9% after placement. Clinical success was not achieved in five patients due to insufficient stent expansion in four patients and stent occlusion in one patient. Only one patient underwent emergency surgery for perforation of the proximal colon, far from where the stent was placed; the rescue procedure was not performed, despite no improvement in proximal dilatation due to insufficient stent expansion. Among the palliation cohort, 15 patients received chemotherapy, including molecular-targeted agents such as bevacizumab. There were no fatal cases related to stent placement. Conclusions: For management of malignant colorectal obstruction, this newly developed SEMS with low axial force and a high axial force zero-border showed high technical and clinical success rates, and an extremely low perforation rate (0.5%).

Percutaneous Metallic Stents in Malignant Biliary Obstruction: Comparison of Nitinol and Wall Stents.

INTRODUCTION: Palliation of malign biliary obstruction is important which is commonly carried out by percutaneous biliary stenting. Our primary aim with this study was assessment of performance of wall stents, and nitinol stents for the palliation of malign biliary obstruction. METHODS: The medical records of 157 patients who underwent biliary stenting in our department between January 1, 1995, and December 31, 2005, were retrospectively analyzed. Technical success, treatment success, mortality in the first 30 days, minor, and major complications were evaluated and compared among the wall stent, and the nitinol stent groups in all patients which constituted the primary study endpoints. Additionally, stent patency, and mean patient survival times after stent implantation were evaluated in patients for whom follow-up information could be obtained. RESULTS: A total of 213 metallic stents were placed in 157 patients. Wall stent was placed in 83 of the patients with mean age, and SD of 60.4 and 13.5. Nitinol stent was placed in 74 of the patients with mean age of 57.8, and SD of 15.5. Gender ratio was equal in both groups. Biliary stent dysfunction was observed in 13 patients in each of nitinol, and wall stent groups throughout the study period. There was no statistical difference among re-occlusion rates (p = 0.91). For the nitinol stent group median primary patency time was 119 days (90-185 days CI 95%), and for the wall stent group median primary patency time was 81 days (60-150 days CI 95%). CONCLUSION: Nitinol stents, and wall stents are safe options that can be safely used in the percutaneous treatment of malignant biliary obstruction with similar treatment and therapeutic success, low complication rates, and patency times that can extend beyond expected survival times.

Short-term and three-year long-term outcomes of laparoscopic surgery versus open surgery for obstructive colorectal cancer following self-expandable metallic stent placement: a meta-analysis.

BACKGROUND: A bridge to surgery (BTS) after self-expandable metallic stent (SEMS) placement is a widely recognized treatment strategy for obstructive colorectal cancer. However, there is still a lack of evidence for the efficacy and safety of laparoscopic surgery following SEMS placement. The aim of this systematic review and meta-analysis was to compare the short-term and long-term outcomes of laparoscopic surgery with those of open surgery following SEMS placement in patients with obstructive colorectal cancer. METHODS: An electronic literature search through to December 2022 was performed to identify studies comparing short-term and long-term outcomes between laparoscopic and open surgery following SEMS placement for obstructive colorectal cancer. The main outcome measures were postoperative complication rates and mortality. Secondary outcome measures were the 3-year recurrence-free survival (RFS) and 3-year overall survival (OS) rates. The meta-analysis was performed using fixed-effect or random-effects methods to calculate odds ratios (ORs) with 95% confidence intervals (95% CIs). RESULTS: The meta-analysis included 15 studies and 883 patients, of whom 467 (52.9%) underwent laparoscopic surgery and 416 (47.1%) underwent open surgery following SEMS placement. The postoperative complication rate was significantly lower in the laparoscopic surgery group than in the open surgery group (OR 0.47, 95% CI 0.32-0.67, P < 0.001). There was no significant difference in the 3-year RFS rate or 3-year OS rate between the laparoscopic and open surgery groups (3-year RFS, OR 0.78, 95% CI 0.50-1.24, P = 0.30; 3-year OS, OR 0.68, 95% CI 0.41-1.12, P = 0.13). CONCLUSION: This meta-analysis found that the short-term outcome was better in patients who underwent laparoscopic surgery following SEMS placement than in those who underwent open surgery. Furthermore, there was no significant difference in long-term outcomes between the two groups. Laparoscopic surgery following SEMS placement may be a safe and effective treatment option for obstructive colorectal cancer.

Risk factors for recurrent biliary obstruction following endoscopic biliary stenting in patients with unresectable ampullary cancer: A multicenter retrospective study.

OBJECTIVES: Unresectable ampullary cancer (AC) is a rare disease entity. The risk factors for recurrent biliary obstruction (RBO) following endoscopic biliary stenting (EBS) for unresectable AC remain unknown. In this study we aimed to evaluate the cumulative RBO rate and to identify risk factors for RBO following palliative EBS in patients with unresectable AC. METHODS: This multicenter retrospective observational study enrolled consecutive patients with unresectable AC who had undergone palliative EBS between April 2011 and December 2021. The cumulative rate of and risk factors for RBO following palliative EBS were evaluated via multivariate analysis. RESULTS: The study analysis comprised 107 patients with a median age of 84 years (interquartile range 79-88 years). Plastic stents (PSs) and self-expandable metal stents (SEMSs) were placed in 53 and 54 patients, respectively. Functional success was accomplished in 104 (97.2%) patients. Of these, RBO occurred in 62 (59.6%) patients, with obstruction and complete/partial migration occurring in 47 and 15 patients, respectively. The median time to RBO was 190 days. Multivariate analysis showed that PS was associated with a higher rate of RBO compared to SEMS (hazard ratio [HR] 2.48; P < 0.01) and that the presence of common bile duct stones/sludge immediately after EBS was an independent risk factor for RBO (HR 1.99; P = 0.04). CONCLUSIONS: The use of SEMS compared to PS during EBS reduced the time to RBO in patients with unresectable AC. Common bile duct stones/sludge immediately after EBS was a risk factor for RBO.

A Bridge to Curative Surgery for Obstructive Colorectal Cancer: Self-expandable Metallic Stent Versus Decompression Tube.

BACKGROUND/AIM: Self-expandable metallic stent (SEMS) placement is becoming the standard bridge-to-surgery (BTS) strategy for potentially curable left-sided obstructive colorectal cancer (OCRC). The study objective was to evaluate the effectiveness of SEMS placement as a BTS strategy for both right- and left-sided OCRC. PATIENTS AND METHODS: We retrospectively compared the short- and long-term outcomes of patients with OCRC who underwent placement of a SEMS versus a trans-nasal/anal decompression tube (DCT). The cohort comprised 57 patients with stage II/III right-sided OCRC (DCT, n=20; SEMS, n=8) or left-sided OCRC (DCT, n=9; SEMS, n=20). The short-term outcomes were the incidence of postoperative complications, rate of laparoscopic surgery, rate of stoma construction, and postoperative hospital stay; long-term outcomes were the 3-year overall survival (OS) and relapse-free survival (RFS). RESULTS: The SEMS group had a higher rate of laparoscopic surgery (85.7% vs. 6.9%, p<0.001), lower rate of stoma construction (10.7% vs. 34.5%, p=0.03), and shorter postoperative hospital stay (14 vs. 17 days, p=0.04) than the DCT group. Both groups had a similar incidence of postoperative complications. The 3-year OS and RFS were also similar in the DCT and SEMS groups for both right-sided OCRC (OS, 75.0% vs. 87.5%, HR=1.51, 95% CI=0.22-10.25, p=0.7; RFS, 65.0% vs. 50.0%, HR=0.97, 95% CI=0.28-3.36, p=0.9) and left-sided OCRC (OS, 88.8% vs. 90.0%, HR=1.19, 95% CI=0.10-14.29, p=0.9; RFS, 77.8% vs. 85.0%, HR=1.03, 95% CI=0.16-6.5, p=0.9). CONCLUSION: SEMS placement is a reasonable BTS strategy for left- and right-sided OCRC that achieves comparable short- and long-term outcomes to DCT insertion.

Efficacy of endoscopic ultrasound-guided gastroenterostomy using self-expandable metallic stent for afferent loop syndrome: A single-center retrospective study.

BACKGROUND AND AIM: Endoscopic ultrasound-guided gastroenterostomy is a procedure used to connect the stomach and dilated afferent loop using a stent under endoscopic ultrasound for afferent loop syndrome. However, the actual efficacy and safety of this procedure remain unclear. Therefore, this retrospective study aimed to evaluate the efficacy and safety of endoscopic ultrasound-guided gastroenterostomy using a laser-cut-type fully covered self-expandable metallic stent and an anchoring plastic stent for afferent loop syndrome. METHODS: Technical and clinical success rates, adverse events, recurrent intestinal obstruction rates, time to recurrent intestinal obstruction, and technical and clinical success rates of re-intervention were evaluated in intended patients who underwent endoscopic ultrasound-guided gastroenterostomy for afferent loop syndrome from October 2018 to August 2022. RESULTS: In 25 intended patients with afferent loop syndrome who intended endoscopic ultrasound-guided gastroenterostomy, the technical success rate was 100% (25/25), whereas the clinical success rate was 96% (24/25). Two patients experienced grade ≥ 3 early adverse events, including one with intra-abdominal abscess and one with hypotension. Both events were attributed to intestinal fluid leakage. No late adverse events were observed. The recurrent intestinal obstruction rate was 32% (8/25), and the median time to recurrent intestinal obstruction was 6.5 months (95% confidence interval: 2.8-not available). The technical and clinical success rates of re-intervention were both 100% (8/8). CONCLUSIONS: Endoscopic ultrasound-guided gastroenterostomy using a fully covered self-expandable metallic stent and an anchoring plastic stent is effective and safe as a treatment procedure for afferent loop syndrome.

Ruptured pseudoaneurysm in a biliary metallic stent in a patient with pancreatic cancer: a case report.

We report a case of an 87 year-old woman who was admitted with jaundice, but had no pain or fever. Contrast-enhanced computed tomography revealed a tumor in the head of the pancreas, which caused distal malignant biliary obstruction. Initial transpupillary drainage by endoscopic retrograde cholangiopancreatography (ERCP) was difficult due to severe biliary stricture caused by the tumor, but cannulation of the pancreatic duct was successful. Pancreatic ductal adenocarcinoma was revealed through cytologic examination of pancreatic juice and the patient underwent percutaneous transhepatic biliary drainage (PTBD). 16 days after the jaundice was resolved, an uncovered Zilver® metallic stent was successfully deployed using a guidewire from the PTBD route, and the patient was discharged with palliative care due to advanced age. However, 54 days after discharge, the patient presented with black vomiting and recurrent jaundice. ERCP revealed an obstructed stent with black debris, and further evaluation revealed a ruptured pseudoaneurysm that branched off the gastroduodenal artery within the metallic biliary stent. Angiography revealed that embolization was successful. The patient recovered and was discharged without further episodes.

Resultados del uso de prótesis endoscópica colorrectal. 15 años de experiencia

Objetivo: Describir morbimortalidad asociada al uso de prótesis colorrectales (PC) e identificar factores asociados a sus complicaciones durante los años 2007 a 2022 en Clínica INDISA. Material y Método: Estudio transversal retrospectivo basado en registro clínico. Resultados: Se instalaron 49 PC con un 100% de éxito de desobstrucción. El 87,8% en colon izquierdo. La etiología principal fue la patología maligna 91,8% y el 85,7% de ellos fueron primarios colorrectales. Se instalaron 34 como tratamiento paliativo (TP), 12 como puente a cirugía electiva (PCE) y 3 por patología benigna. La tasa de complicaciones fue de 26,5% (7 estenosis, 4 perforaciones y 2 migraciones). La mortalidad asociada fue de 4,1% (2 pacientes). El grupo de complicados fue más joven, con etapas oncológicas más avanzadas y con estenosis en rectosigmoides(p < 0,005). Los menores de 50 años tuvieron 5 veces más riesgo de alguna complicación (OR = 5,0;IC95%:1,09-23,0; p = 0,039). Discusión: El uso de PC tiene baja morbimortalidad. Su uso principal es como TP o PCE en obstrucción colorrectal maligna, con alta tasa de desobstrucción. Está asociado con menor morbilidad que la cirugía de urgencia, menor tasa de ostomía y mayor cosecha ganglionar. La instalación como puente se asocia además a mayor tasa de anastomosis primaria. Nuestra serie mostró mayor tasa de complicación en aquellos con tumores avanzados y más jóvenes. Conclusión: El uso de PC es seguro y con baja morbimortalidad. La principal indicación es en neoplasia colorrectal obstructiva como TP. Tienen mayor riesgo de complicación los pacientes jóvenes y los tumores colorrectales avanzados con ganglios peri tumorales.

Objective: To describe morbidity and mortality associated with colorectal prostheses (CP) and identify factors associated with their complications during the 2007 to 2022 at INDISA Clinic. Material and Method: Retrospective cross-sectional study based on clinical registry. Results: 49 CPs were installed with 100% clearing success. 87.8% in left colon. The main etiology was malignant 91.8% and 85.7% were primary colorectal. 34 were installed with palliative intention, 12 as a bridge to elective surgery (BTS) and 3 for benign pathology. There were 13 (26.5%) patients with adverse effects (7 strictures, 4 perforations and 2 migrations). Associated mortality was 4.1% (2 patients). The complicated group was younger, with more advanced oncological stages and rectosigmoid stenosis (p < 0.005). Those under 50 years of age had 5 times higher risk of some complication (OR = 5.0; 95% CI: 1.09-23.0; p = 0.039). Discussion: The use of CPs has low short-term morbidity and mortality. Its main use is as palliative treatment or BTS in malignant colorectal obstruction. It's a high clearance rate. It is associated with less morbidity than emergency surgery, a lower ostomy rate, and a higher lymph node harvest. Installation as a bridge is also associated with a higher rate of primary anastomosis. Our group showed a higher complication rate in those with advanced and younger tumors. Conclusion: The use of CPs is safe, with low morbidity and mortality. The main indication is in obstructive colorectal neoplasia as palliative treatment. Young patients and advanced colorectal tumors with peritumoral nodes have a higher risk of complications.

Clinical Outcomes of Secondary Duodenal Self-Expandable Metallic Stenting for Duodenal Stent Dysfunction in Patients with Malignant Duodenal Obstruction: A Retrospective Multicenter Study.

Background/Aims: Malignant duodenal obstruction has become more common with the development of palliative therapies.The outcomes of endoscopic ultrasound-guided gastrojejunostomy (EUS-GJ) are comparable to those of surgical gastrojejunostomy or duodenal stenting. However, EUS-GJ is technically challenging. Duodenal self-expandable metallic stent (SEMS) placement is popular; however, obstructions are common. Duodenal SEMS obstruction can be managed with the insertion of a second SEMS in a stent-in-stent manner. Therefore, we aimed to analyze the clinical outcomes of secondary duodenal SEMS placement in patients with malignant duodenal obstruction. Methods: We retrospectively analyzed the data of patients who underwent secondary duodenal stent insertion for duodenal stent dysfunction between January 2016 and December 2021. The primary outcome was stent patency. The secondary outcomes were clinical success, factors associated with dysfunction, patient survival, and adverse events. Results: A total of 109 patients were included. The mean age was 64.4±11.2 years, and 63 patients (57.8%) were male. Ninety-two patients (84.4%) had pancreaticobiliary cancer. Clinical success was achieved in 94 cases (86.2%). Twenty-three patients experienced stent dysfunction with 231 days of median stent patency (95% confidence interval [CI], 169 to not available). After a multivariable Cox hazard analysis of stent patency, the Eastern Cooperative Oncology Group performance status (hazard ratio [HR], 2.13; 95% CI, 1.20 to 3.81; p=0.010) and the first stent patency ≥6 months (HR, 0.33; 95% CI, 0.11 to 0.95; p=0.050) remained significant associated factors. Adverse events occurred in five patients (4.6%). Conclusions: Secondary duodenal stent insertion is a viable option for first duodenal stent obstruction. Further comparative studies involving surgery or EUS-GJ for obstructed duodenal stents are warranted.

Long-Term Outcomes of Self-Expandable Metallic Stents as a Bridge to Surgery for Obstructive and Symptomatic Primary Tumors of Stage IV Colorectal Cancer: A Propensity-Score Analysis.

Background: Self-expandable metallic stent (SEMS) was introduced for the treatment of obstructive colorectal cancer (CRC) a few decades ago. However, its long-term outcomes remain controversial, especially for stage IV CRC. The aim of this study was to clarify the outcomes of SEMS as a "bridge to surgery" (BTS) for obstructive and symptomatic primary tumors in stage IV CRC by one-to-one propensity-score matching. Materials and Methods: This retrospective cohort study was conducted at a single center from January 2007 to December 2017. Patients with obstructive and symptomatic primary tumors of stage IV CRC underwent primary resection (PR) or placement of a SEMS as a BTS. They were divided into SEMS and PR groups, and their short- and long-term outcomes were compared. Results: In total, 52 patients were reviewed (SEMS group, 21; PR group, 31). Sixteen patients in both groups were matched using propensity scores. Patients in the SEMS group more frequently underwent laparoscopic surgery than those in the PR group (75% versus 19%, P = .004). The two groups showed no significant differences in perioperative and pathological outcomes. The 5-year overall survival was not significantly different between groups (29% versus 20%, P = .53). Conclusions: As a BTS, the use of SEMS for obstructive and symptomatic primary tumors in CRC stage IV can be a comparable option to PR in terms of short- and long-term outcomes, and would be less invasive with respect to surgical procedures.

Covered self-expandable metallic stent placement for tumor bleeding from duodenal invasion in patients with unresectable pancreatic cancer.

Patients with unresectable pancreatic cancer often present with duodenal bleeding, a potentially life-threatening complication. In our case series of six unresectable pancreatic cancer patients with tumor bleeding, we explored the efficacy and safety of placement of a covered self-expandable metallic stent in the duodenum as a treatment option; we achieved a hemostasis rate of 67% (4/6), with a rebleeding rate of 50% (2/4). No complications occurred with stent placement, except for food impaction in one patient. Covered self-expandable metallic stent placement is a moderately effective treatment option for tumor bleeding in patients with unresectable pancreatic cancer. Although its hemostatic efficacy is limited, covered self-expandable metallic stent placement is safe and beneficial in some cases, warranting consideration in this disease setting with limited treatment options.

Self-expandable metallic stents may be more efficient than balloon dilatation alone for esophageal stricture after circumferential endoscopic submucosal dissection: a retrospective cohort study in China.

INTRODUCTION: Self-expandable metallic stents (SEMSs) can be used to treat esophageal stricture after circumferential endoscopic submucosal dissection (ESD), but its efficacy and placement timing remain to be determined. In this study, the treatment time and number of dilatations were compared between the SEMS placement group and the balloon dilatation (BD) group to clarify the efficacy and placement time of SEMSs in the treatment of esophageal stricture after circumferential esophageal ESD. METHODS: This was a retrospective cohort study. Patients with esophageal stricture after circumferential ESD between January 2015 and January 2020 were included. Data on the patients' demographic characteristics, esophageal lesion-related factors, esophageal stricture occurrence, and measures taken to treat the stricture were collected. The primary outcome was the treatment time, and the secondary outcome was the number of dilatations. RESULTS: The total number of dilatations was 30 in the SEMS group and 106 in the BD group. The average number of dilatations in the SEMS group (1.76 ± 1.64) was significantly lower than that in the BD group (4.42 ± 5.32) (P = 0.016). Among the patients who underwent SEMS placement first had a shorter treatment time (average 119 days) than those who underwent BD first (average 245 days) (P = 0.041), and the average number of dilatations inpatients who underwent SEMS placement first (0.71 ± 1.07) was significantly lower than that in the patients who underwent BD first (2.5 ± 1.54). CONCLUSION: SEMSs were more efficient in the treatment of esophageal stricture in a cohort of patients after circumferential esophageal ESD.

Evaluating optimal bilateral biliary stenting in endoscopic reintervention after initial plastic stent dysfunction for unresectable malignant hilar biliary obstruction: Retrospective cross-sectional study.

OBJECTIVES: The placement of plastic stents (PS), including intraductal PS (IS), is useful in patients with unresectable malignant hilar biliary obstruction (UMHBO) because of patency and ease of endoscopic reintervention (ERI). However, the optimal stent replacement method for PS remains unclear. METHODS: This retrospective study included 322 patients with UMHBO. Among them, 146 received PS placement as initial drainage (across-the-papilla PS [aPS], 54; IS, 92), whereas 75 required ERI. Eight bilateral aPS, 21 bilateral IS, and 17 bilateral self-expandable metallic stent (SEMS) placements met the inclusion criteria. Rates of technical and clinical success, adverse events, recurrent biliary obstruction (RBO), time to RBO (TRBO), overall survival, and secondary ERI were compared. RESULTS: There were no significant intergroup differences in rates of technical or clinical success, adverse events, RBO occurrence, or overall survival. The median TRBO was significantly shorter in the aPS group (47 days) than IS (91 days; P = 0.0196) and SEMS (143 days; P < 0.01) groups. Median TRBO did not differ significantly between the IS and SEMS groups (P = 0.44). On Cox multivariate analysis, the aPS group had the shortest stent patency (hazard ratio 2.67 [95% confidence interval 1.05-6.76], P = 0.038). For secondary ERI, the median endoscopic procedure time was significantly shorter in the IS (22 min) vs. SEMS (40 min) group (P = 0.034). CONCLUSIONS: Bilateral IS and SEMS placement featured prolonged patency after first ERI. Because bilateral IS placement is faster than SEMS placement and IS can be removed during secondary ERI, it may be a good option for first ERI.

Pancreatic Pseudocyst after Fully Covered Self-expandable Metallic Stent Placement: A Case Report.

A 70-year-old woman presented with stage III pancreatic head cancer. After endoscopic sphincterotomy, a fully covered self-expandable metallic stent (FCSEMS) was placed in the common bile duct to manage jaundice. The patient developed a fever and abdominal pain 40 days after stent placement, with a suspected diagnosis of infected pancreatic pseudocyst. Purulent discharge from the papilla was observed during FCSEMS removal, and pancreatography revealed a pseudocyst connected to the main pancreatic duct. The pancreatic pseudocyst resolved after transpapillary drainage. Pancreatic pseudocysts should be suspected after biliary FCSEMS placement, and prompt removal and endoscopic drainage of the FCSEMS should be considered.

Localized Photodynamic Therapy Using a Chlorin e6-Embedded Silicone-Covered Self-Expandable Metallic Stent as a Palliative Treatment for Malignant Esophageal Strictures.

Localized photodynamic therapy (PDT) uses a polymeric-photosensitizer (PS)-embedded, covered self-expandable metallic stent (SEMS). PDT is minimally invasive and a noteworthy potential alternative for treating esophageal strictures, where surgery is not a viable option. However, preclinical evidence is insufficient, and optimized irradiation energy dose ranges for localized PDT are unclear. Herein, we validated the irradiation energy doses of the SEMS (embedded in a PS using chlorin e6 [Ce6] and covered in silicone) and PDT-induced tissue changes in a rat esophagus. Cytotoxicity and phototoxicity in the Ce6-embedded SEMS piece with laser irradiation were significantly higher than that of the silicone-covered SEMS with or without laser and the Ce6-embedded silicone-covered SEMS without laser groups (all p < 0.001). Moreover, surface morphology, atomic changes, and homogeneous coverage of the Ce6-embedded silicone-covered membrane were confirmed. The ablation range of the porcine liver was proportionally increased with the irradiation dose (all p < 0.001). The ablation region was identified at different irradiation energy doses of 50, 100, 200, and 400 J/cm2. The in vivo study in the rat esophagus comprised a control group and 100, 200, and 400 J/cm2 energy-dose groups. Finally, histology and immunohistochemistry (TUNEL and Ki67) confirmed that the optimized Ce6-embedded silicone-covered SEMS with selected irradiation energy doses (200 and 400 J/cm2) effectively damaged the esophageal tissue without ductal perforation. The polymeric PS-embedded silicone-covered SEMS can be easily placed via a minimally invasive approach and represents a promising new approach for the palliative treatment of malignant esophageal strictures.

Endoscopic ultrasound-guided hepaticoduodenostomy versus percutaneous drainage for right intrahepatic duct dilatation in malignant hilar obstruction.

BACKGROUND AND AIM: Endoscopic ultrasound (EUS)-guided biliary drainage is being increasingly performed as an alternative to percutaneous transhepatic biliary drainage (PTBD) to treat malignant hilar obstruction (MHO) after failed endoscopic retrograde cholangiopancreatography (ERCP). However, no study has compared EUS-guided hepaticoduodenostomy (EUS-HDS) with PTBD for right intrahepatic duct (IHD) obstruction after failed ERCP in patients with unresectable MHO. METHODS: We retrospectively reviewed the data of consecutive patients with right IHD obstruction developed by unresectable MHO who underwent EUS-HDS or PTBD after a previous placement of a stent in the left and/or right IHD between March 2018 and October 2021. Technical success, clinical success, stent or tube-related adverse events, frequency of reintervention, and stent patency were evaluated. RESULTS: A total of 42 patients (18 EUS-HDS, 24 PTBD) were analyzed. Both groups did not show significant differences in technical success (EUS-HDS, 94% vs PTBD, 100%; P = 0.429), clinical success (83% vs 83%; P = 0.999), early adverse events (24% vs 46%; P = 0.144), and stent or tube-related late adverse events (29% vs 54%; P = 0.116). During follow-up, the EUS-HDS group had a longer median duration of patency (131 days vs 58.5 days; P = 0.041), and lower mean frequency of reinterventions per patient (0.35 vs 1.92; P = 0.030) than the PTBD group. CONCLUSIONS: EUS-HDS showed comparable efficacy and safety to PTBD for drainage of the right biliary system and produced longer duration of patency and lower frequency of reinterventions in patients with unresectable MHO.

Prevention of Migration of Esophageal Self-Expandable Metallic Stents Using Endoscopic Clips.

Background and Objectives: Esophageal stenting with self-expandable metallic stents (SEMS), for both benign and malignant reasons, has been widely practiced for decades, but migration still remains the most common complication of the procedure. In this report we aim to review our experience and results in stent fixation with clips. Materials and Methods: We present 18 patients who underwent esophageal stenting for both benign and malignant reasons. The SEMSs used were partially covered and were fixated with two to four through the scope hemostatic clips in the proximal end of the prothesis. The procedure was performed only on patients with a high risk of migration of the stent. Results: Migration occurred in only one of the above-mentioned patients and was treated with stent repositioning. The other adverse events that occurred were related to tumor growth in patients with malignant diseases. Conclusions: Clip fixation of an esophageal self-expandable metallic stent in cases considered high-risk for migration is a safe procedure. It reduces the migration rate significantly for both benign and malignant indications.

Efficacy and Safety of Self-Expandable Metallic Stent Placement for Malignant Esophageal Fistula.

Patients with malignant esophageal fistulas often experience dysphagia and infection, resulting in poor prognoses. Self-expandable metallic stent (SEMS) placement is a palliative treatment option; however, its efficacy and safety are unclear. We aimed to determine the efficacy and safety of SEMS placement for malignant esophageal fistulas. We retrospectively investigated patients who underwent SEMS placement for malignant esophageal fistulas between 2013 and 2022 at the Cancer Institute Hospital. Dysphagia scores (DSs) before and after SEMS placement, adverse events, and overall survival from SEMS placement until death were evaluated. A total of 17 patients underwent SEMS placement, including 12 and 5 patients with esophageal and lung cancers, respectively. Prior treatments included chemoradiotherapy (n = 11), radiotherapy (n = 4), and chemotherapy (n = 4); two patients underwent palliative radiotherapy after chemotherapy. All procedures were technically successful. After SEMS placement, 14 (82.4%) patients were able to consume semisolid or solid food (DS ≤ 2). Major adverse events were encountered in only one case. The median survival time after SEMS placement was 71 days (range 17-247 days). SEMS placement allowed most patients to resume oral intake with a low rate of major adverse events. SEMS placement is a reasonable palliative treatment option for patients with malignant fistulas who have poor prognoses.

Radiofrequency ablation via an implanted self-expandable metallic stent to treat in-stent restenosis in a rat gastric outlet obstruction model.

Background: In-stent restenosis caused by tissue hyperplasia and tumor growth through the wire meshes of an implanted self-expandable metallic stent (SEMS) remains an unresolved obstacle. This study aimed to investigate the safety and efficacy of SEMS-mediated radiofrequency ablation (RFA) for treating stent-induced tissue hyperplasia in a rat gastric outlet obstruction model. Methods: The ablation zone was investigated using extracted porcine liver according to the ablation time. The optimal RFA parameters were evaluated in the dissected rat gastric outlet. We allocated 40 male rats to four groups of 10 rats as follows: group A, SEMS placement only; group B, SEMS-mediated RFA at 4 weeks; group C, SEMS-mediated RFA at 4 weeks and housed until 8 weeks; and group D, SEMS-mediated RFA at 4 and 8 weeks. Endoscopy and fluoroscopy for in vivo imaging and histological and immunohistochemical analysis were performed to compare experimental groups. Results: Stent placement and SEMS-mediated RFA with an optimized RFA parameter were technically successful in all groups. Granulation tissue formation-related variables were significantly higher in group A than in groups B-D (all p < 0.05). Endoscopic and histological findings confirmed that the degrees of stent-induced tissue hyperplasia in group D were significantly lower than in groups B and C (all p < 0.05). Hsp70 and TUNEL expressions were significantly higher in groups B-D than in group A (all p < 0.001). Conclusion: The implanted SEMS-mediated RFA successfully managed stent-induced tissue hyperplasia, and repeated or periodic RFA seems to be more effective in treating in-stent restenosis in a rat gastric outlet obstruction model.