Self-expandable Metal Stent Insertion Research Articles

Low-pressure self-expandable metal stent insertion for obstructive colon cancer using water and gel immersion.

Low-pressure self-expandable metal stent insertion for obstructive colon cancer using water and gel immersion.

Efficacy and safety of self-expandable metallic stents for management of benign gastric outlet obstruction-A prospective study.

We aimed at evaluating the safety and efficacy of self-expandable metallic stent (SEMS) insertion for managing patients with benign gastric outlet obstruction (GOO). This prospective interventional study included 23 patients. All consecutive treatment-naïve symptomatic patients with benign GOO were recruited. Fully covered SEMS were deployed across the stricture under fluoroscopic and endoscopic guidance. Technical success, clinical success and sustained treatment response (STR) were assessed. Technical success was defined as the successful deployment of SEMS at the desired anatomic location. Clinical success was defined as the resolution of symptoms and an increase in Gastric Outlet Obstruction Scoring System (GOOSS) of at least 1 point from the baseline score on Day 7. STR was assessed at four and eightweeks post stent removal in patients who had a response at week four. Factors associated with stent migration and non-response at week four were also assessed. The median age of the study population was 30years (range 19-65years). Males constituted 65.22%. Most patients presented with vomiting (100%) and abdominal pain (95.65%). Peptic stricture was most common etiology for GOO (60.9%) followed by tubercular (26.1%) and corrosive (13%). Most common site of obstruction was junction of first and second part of duodenum (69.57%) followed by pyloric (30.43%). Median length of stricture was 2cm (range 1.5-4). Technical success was achieved in all 23 patients (100%). Clinical success was achieved in 21 patients (91.3%). Response at Day 28 was seen in 20 patients (86.95%). Eighteen of 20 (90%) patients who had a response at week four had STR at week four and week eight after stent removal. Stent migration occurred in five (21.7%) patients. On univariate analysis, stricture length, calibre and stent length were found to predict migration. Fully covered SEMS was an effective and safe management modality in patients with benign GOO. Stent migration remains a troublesome disadvantage.

Comparative study between biliary covered self-expandable metal stent and conventional endoscopic bile drainage treatment in endoscopic retrograde cholangiopancreatography-related Stapfer type II retroperitoneal perforations.

Perforation is one of the most serious complications of endoscopic retrograde cholangiopancreatography (ERCP). Conventional nonsurgical endoscopic treatments including intravenous antibiotic administration and plastic endoscopic biliary drainage are generally approved for the treatment of ERCP-related Stapfer type II perforation (perivaterian type). Biliary covered metal stent placement has recently been reported to have favorable outcomes in ERCP-related Stapfer type II perforations. We aimed to compare the outcomes of conventional endoscopic bile drainage and biliary covered self-expandable metal stent (SEMS) insertion in patients with Stapfer type II perforation. Medical records of patients who underwent ERCP at Kyungpook National University Hospital in Daegu from 2011 to 2022 were retrospectively reviewed. A total of 8,402 ERCP procedures were performed in our hospital. Sixty-six ERCP-related perforations (0.78%) were identified. Among them, 37 patients (56.1%) who had Stapfer type II perforations were enrolled. Thirteen and twenty-four patients received biliary covered SEMS insertion and conventional endoscopic bile drainage treatments, respectively. No significant differences were observed in the clinical success rate (92.3% vs. 91.7%, p = 1.000), hospital stay (9.46 ± 5.97 vs. 13.9 ± 13.2 days, p = 0.258), and post-ERCP-related fasting time (5.4 ± 3.4 vs 4.3 ± 3.0 days, p = 0.305). Complications including bleeding, post-ERCP pancreatitis, fever, and death were not significantly different between the two groups. The conventional endoscopic bile drainage group took less time for ERCP than the SEMS group (11.5 ± 5.2 vs. 18.5 ± 11.2 min, p = 0.013). Compared with the conventional endoscopic bile drainage treatment method, biliary covered SEMS did not improve patient outcomes in ERCP-related Stapfer type II perforations.

A novel method of bilateral biliary decompression by EUS-guided hepaticogastrostomy with bridging stenting using the partial stent-in-stent method for reintervention of multiple metal stent failure

Video 1A novel method of bilateral biliary decompression by EUS-guided hepaticogastrostomy with bridging stenting using the partial stent-in-stent method for reintervention of multiple metal stent failure.We report a case in which anterior and posterior drainage was performed using the partial stent-in-stent method via the transpapillary approach. The patient had a bismuth type IV biliary obstruction, but only the right hepatic lobe was drained due to obstruction of the left portal vein. For the recurrent stent dysfunction, the patient underwent placement of a plastic stent within an uncovered self-expanding metal stent to correct stent dysfunction. A 7F plastic stent inside a metal stent is shown.The patient later experienced stent failure and jaundice due to tumor progression and was admitted for plastic stent replacement. Neither imaging results nor symptoms suggested duodenal stenosis. The transpapillary approach was attempted first but was unsuccessful. Duodenoscopy was challenging to perform because of duodenal stenosis. Fluoroscopy confirmed the duodenal stenosis. The plastic stent was extracted using an upper endoscope. Multiple uncovered metal stents are shown (1 stent in the anterior bile duct and 2 stents in the posterior bile duct). Jaundice did not resolve despite plastic stent removal.The patient refused to undergo percutaneous biliary drainage, so a decision was made to perform an EUS-guided hepaticogastrostomy (HGS) instead. The left bile duct was observed in the stomach. The left bile duct was punctured with a 19-gauge FNA needle. A 0.025-inch hydrophilic guidewire was directed into the left bile duct. Enhancement of the bile duct showing malignant hilar biliary obstruction (bismuth IV) is seen. Insertion of the guide wire into the posterior bile duct is shown.The stent mesh was then dilated using a balloon dilator. However, there was difficulty inserting the catheter. Additional dilation was performed using a spiral dilator. This instrument is a tapered tip dilator that fits into 0.025-inch guidewires and is expandable to 7F. Insertion of a second guidewire with a larger caliber was done to straighten the bile duct and help stabilize stent insertion. A 0.035-inch hydrophilic guidewire into the posterior bile duct using a double-lumen cannula and insertion of a 0.025-inch hydrophilic guidewire into the anterior bile duct are shown.The stent mesh was then dilated using a spiral dilator. A metal stent was placed through the anterior bile duct at a steep angle. Insertion and deployment of the first uncovered self-expanding metal stent (8× 60mm) from the anterior bile duct into the left bile duct is shown. Multiple metal stents were implanted into the hilar area, and the new stent was placed using the partial stent-in-stent method to prevent overexpansion. Guidewire seeking the posterior bile duct from inside the deployed stent through the stent mesh is shown.The stent mesh was then dilated using a balloon dilator. Insertion and deployment of an uncovered self-expanding metal stent (8× 60mm) from the posterior bile duct to the left bile duct using the partial stent-in-stent method is shown. Enhancement of the bile duct shows drainage from the right bile duct. The fistula of the HGS was only dilated with the spiral dilator. The risk of bile leakage was low, so we decided to implant a plastic stent. A 7F× 15-cm plastic stent was placed from the posterior bile duct into the stomach. Anterior and posterior segment drainage by EUS-HGS with bridging stenting using the partial stent-in-stent method is shown, with left segment drainage by EUS-HGS with the plastic stent.We performed EUS-HGS on a patient with multiple metal stents in place. There were no adverse events, and total bilirubin levels were reduced by more than half within 2 weeks. Six months have passed without stent dysfunction.

Type 2 biliary perforation successfully managed with early insertion of self-expandable metal stent

Perforations after endoscopic retrograde colangiopancreatography (ERCP) are divided into four types. Type 1 refers to the duodenum, type 2 the periampullary region, type 3 the bile duct itself, and type 4 the observation of retroperitoneal free air on cross-sectional imaging. The treatment of type 2 biliary perforations remains debatable. We present a patient who was successfully treated with a self-expandable metal stent (SEMS) without the need for surgery or any complications.

Performance of biliary stents in malignant biliary strictures.

Endoscopic stenting is a commonly applied method of treatment in patients with malignant biliary strictures. It involves the use of self‑expandable metal stents (SEMSs) or plastic stents (PSs). The aim of the study was to compare the effectiveness of SEMSs and PSs in the endoscopic drainage of malignant strictures of the biliary tree and its sequels for future optimalization of this treatment method. Data on 618 consecutive patients with malignant biliary stricture, in whom 1271endoscopic retrograde cholangiopancreatography procedures with biliary stenting have been performed in the years 2012-2017 with at least 3‑year follow‑up, were retrospectively derived from a hospital database. The main indications for stenting were pancreatic cancer (37%) and cholangiocarcinoma (34%). The use of SEMSs resulted in a greater decline of serum bilirubin as compared with PSs (37% vs 32% of baseline concentration; P = 0.01). Consequently, hospital stay was shorter by more than 2 days (mean [SD], 9.5 [5.6] vs 11.8 [7.9] days; P <0.001). The median (interquartile range) patency time of SEMSs was more than 2 times longer than for PSs (118 [56-232] days vs 46 [18-97] days; P <0.001), and procedure‑related complications were less frequent (19.3% vs 12.9%, respectively in the SEMS and PS group; P = 0.001). SEMSs proved also to be more cost‑effective; the hospital profit was 1375 USD for a single hospitalization with SEMS insertion. In patients with malignant strictures of the biliary tree SEMSs outperform PSs. SEMSs should be used as a treatment of choice for biliary drainage in that group of patients.

Short-term and long-term oncologic outcomes of self-expandable metallic stent compared with tube decompression for obstructive colorectal cancer: a systematic review and meta-analysis.

Patients with obstructive colorectal cancer managed by emergency surgery show high morbidity, mortality, and stoma formation rates. Decompression modalities, including the self-expandable metallic stent (SEMS) and tube drainage (TD), have been used to improve surgical outcomes. However, there have been limited studies comparing the 2 modalities. We performed a meta-analysis on short- and long-term outcomes between SEMS and TD. PubMed, EMBASE, Cochrane Library, and Google Scholar were searched. Data were pooled, and the overall effect size was calculated using random effect models. Outcome measures were perioperative short-term and 3-year survival outcomes. We included 20 nonrandomized studies that examined 2,047 patients in the meta-analysis. The meta-analysis showed SEMS had better short-term outcomes in clinical success rate, decompression-related complications, laparoscopic surgery rate, stoma formation rate, and postoperative complication rate with a relative risk (RR) of 0.36 (95% confidence interval [CI], 0.24-0.54; I2 = 20%), 0.32 (95% CI, 0.20-0.50; I2 = 0%), 0.47 (95% CI, 0.34-0.66; I2 = 87%), 0.34 (95% CI, 0.24-0.49; I2 = 52%), and 0.70 (95% CI, 0.54-0.89, I2 = 28%), respectively. However, there was no significant difference between the 2 groups in 3-year overall survival (RR, 0.99; 95% CI, 0.77-1.27; I2 = 0%). Although the long-term oncologic impact of SEMS is still unclear compared with TD, the results of this meta-analysis may suggest that SEMS insertion can be performed more successfully and safely and may have benefits for short-term perioperative outcomes compared with TD. Further studies are warranted to provide more definitive survival results.

Aspirin exposure and its association with metal stent patency in malignant distal biliary obstruction: a large international multicenter propensity score–matched study

Background and AimsStent dysfunction is common following endoscopic retrograde cholangiopancreatography (ERCP) with self-expanding metal stent (SEMS) insertion in malignant distal biliary obstruction (MDBO). Chronic aspirin exposure (ASA-E) has been previously shown to potentially decrease this risk. We aim to further ascertain the protective effect of ASA and to identify other predictors of stent dysfunction. MethodMulticenter retrospective cohort study (9 Canada and 1 US). MDBO who underwent ERCP-SEMS between 01/2014-12/2019 were included and divided into two cohorts: ASA-E and ASA unexposed (ASA-U). Propensity score-matching (PSM) was performed to limit selection bias. Matched variables included: age, sex, tumor stage, and type of metal stent. The primary outcome was the hazard rate of stent dysfunction. A multivariable Cox proportional hazards model was used to identify independent predictors of stent dysfunction. Results1,396 patients were assessed. Following PSM a total of 496 patients were analyzed (248 ASA-E, 248 ASA-U). ERCP-SEMS was associated with high clinical success of 82.2% in ASA-E and 81.2% in ASA-U, p=0.80. A total of 184 patients had stent dysfunction wth a mean stent patency time of 229.9 ± 306.2 days and 245.4 ± 241.4 days in ASA-E and ASA-U, resepectively (p=0.52). On multivariable analysis, ASA-E did not protect against stent dysfunction with a hazard ratio of 1.25 (95% confidence interval, CI: 0.96; 1.63). Pancreatic cancer etiology (HR 1.36, 95% CI:1.15-1.61) predicted stent dysfunction while cancer therapy was protective (HR 0.73, 95% CI: 0.55; 0.96). The use of chronic ASA was not associated with an increased risk for adverse events including bleeding, post-ERCP pancreatitis, and perforation. ConclusionIn this large, multicenter study utilizing propensity score-matching, chronic exposure to ASA did not protect against stent dysfunction in MDBO. Instead, the analysis revealed that the etiology of pancreatic cancer was an independent predictor of stent dysfunction while cancer therapy was protective.

Two Cases of Life-Threatening Hemobilia Following Removal of Biliary Stents Treated with Covered Self-Expandable Metal Stents

Biliary stent removal can cause hemobilia due to injury to the adjacent vessel, but it is rarely reported. If significant hemobilia occurs during stent removal, samesession covered self-expandable metal stent (CSEMS) insertion may be useful as a rescue or bridge therapy before angiography. Here, we report two cases of lifethreatening hemobilia following stent removal successfully treated by CSEMS. The first case was a Klatskin tumor bismuth type IV patient who required biliary stenting for resolving malignant biliary obstruction. The second case was a hepatocellular carcinoma patient who had undergone multiple transarterial chemoembolization and required biliary stents for liver abscess. In this situation, inserting a CSEMS at a higher level than the expected bleeding site and recognizing stenting as a temporary therapy with its limitations are important. Also, it is crucial to consider pre-procedural imaging in high-risk patients, and perform post-procedural imaging to evaluate for ongoing bleeding or vascular abnormalities.

Colorectal self-expanding metal stent insertion using a small-caliber tapered transparent hood and electrolyte-free gel.

Colorectal self-expanding metal stent insertion is a useful procedure to treat acute colorectal obstruction caused by advanced colorectal cancer; however, guidewire perforation has been reported to occur as a result of inadequate endoscopic visibility [1] [2]. It is therefore important to maintain endoscopic visibility of the stricture to allow safe insertion of the colorectal stent. A method to maintain endoscopic visibility using an electrolyte-free gel (Viscoclear; Otsuka Pharmaceutical Factory) has recently been reported [3] [4]; however, it is difficult to maintain proper endoscopic visibility when the endoscopic hood has a large volume, as in the case of a conventional transparent hood. We previously reported a technique to obtain an appropriate field of view under saline immersion conditions using a calibrated, small-caliber tip, transparent hood (CAST hood; TOP, Tokyo, Japan) that has a tapered tip ([Fig. 1]) [5]. Herein, we report the use of a novel technique for colorectal stent insertion using this small-caliber tapered transparent hood and electrolyte-free gel ([Video 1]).

Self-expanding metal stents for the treatment of malignant colon obstruction from extra-colonic malignancy versus intra-colonic malignancy: a systematic review and meta-analysis.

The relative utility of self-expanding metal stent (SEMS) insertion for malignant colon obstruction (MCO) due to extra-colonic malignancy (ECM) versus intra-colonic malignancy (ICM) is understudied. A systematic search was done from inception-April 2021 to identify reports of safety and efficacy of SEMS insertion for the treatment of MCO-ECM versus MCO-ICM. A meta-analysis of proportions, comparative meta-analysis to compute relative risks (RR), and mean differences (MD) was performed. Subgroup analyses and influence analyses were conducted. The certainty in estimates of effect(s) was assessed using the GRADE approach. Eight non-randomized studies were identified; 46% (39-53%) and 63% (59-67%) of patients in the ECM and ICM groups were male. Most obstructions were in the rectosigmoid colon in both ECM and ICM groups. SEMS insertion in MCO-ECM was associated with an increased risk of technical failure compared to MCO-ICM (RR 2.92; 1.13-7.54; Certainty: Very Low). Risk of clinical failure of SEMS was higher in MCO-ECM compared to MCO-ICM (RR 2.88; 1.58-2.52; Certainty: Very Low). The risk of clinical failure remained significant throughout the influence analysis, as well as on subgroup analysis. There was no significant difference in the risk of adverse events or luminal perforation with SEMS insertion among patients with MCO-ECM and MCO-ICM. On influence analysis, removal of one study unveiled a significant increase in the risk of luminal perforation in MCO-ECM (RR 3.22; 1.44-7.19; p = 0.004). SEMS for MCO-ECM may have a technical success rate comparable to or questionably worse than MCO-ICM, with low certainty in estimate of effects. SEMS deployment in MCO-ECM carries a higher risk of clinical failure, with a questionably higher risk of luminal perforation.

Oncologic safety of colonic stenting as a bridge to surgery in left-sided malignant colonic obstruction: Current evidence and prospects

Approximately 7%-29% of patients with colorectal cancer present with colonic obstruction. The concept of self-expandable metal stent (SEMS) insertion as a bridge to surgery (BTS) is appealing. However, concerns on colonic stenting possibly impairing oncologic outcomes have been raised. This study aimed to review current evidence on the short- and long-term oncologic outcomes of SEMS insertion as BTS for left-sided malignant colonic obstruction. For short-term outcomes, colonic stenting facilitates a laparoscopic approach, increases the likelihood of primary anastomosis without a stoma, and may decrease postoperative morbidity. However, SEMS-related perforation also increases local recurrence and impairs overall survival. Moreover, colonic stenting may cause negative oncologic outcomes even without perforation. SEMS can induce shear forces on the tumor, leading to increased circulating cancer cells and aggressive pathological characteristics, including perineural and lymphovascular invasion. The conflicting evidence has led to discordant guidelines. Well-designed collaborative studies that integrate both oncologic outcomes and data on basic research (e.g., alteration of circulating tumors) are needed to clarify the actual benefit of colonic stenting as BTS.

A tissue attached to self-expandable metal stents for biliary stricture could be useful to find malignancy

Biliary strictures can have several benign or malignant causes. We attempted to determine the usefulness of establishing a diagnosis using self-expandable metal stents (SEMS) in a prospective series of patients with suspected malignant biliary obstruction. Data of patients who underwent SEMS removal from August 2016 to December 2019 were collected. During this period, 55 patients underwent endobiliary biopsy and SEMS insertion and removal. Fifty-five consecutive patients (mean age, 69 years; range 53–90 years) were enrolled, and of these, 37 were male and 18 were female. A final diagnosis was established using biopsy specimens in 37 cases (67.3%) and surgical specimens in 6 cases (10.9%), with 12 cases (21.8%) diagnosed on radiological follow-up. The final diagnoses included malignancy in 34 cases (61.8%) and benign stricture in 21 cases (38.2%). Endobiliary biopsy had a sensitivity and specificity of 44.1% and 95.2%, whereas SEMS cytology had a sensitivity and specificity of 52.9% and 100%, respectively. Combining endobiliary biopsy and/or SEMS cytology yielded a sensitivity and specificity of 73.5% and 95.2%, respectively. (1) The use of biopsy results alone as a diagnostic tool yielded an area under the receiver operating characteristic curve (AUC) of 0.70 (0.60–0.79). (2) The addition of SEMS to the biopsy results yielded an AUC of 0.86 (0.78–0.94). (3) The addition of CA 19–9 levels to the biopsy results yielded an AUC of 0.81 (0.71–0.94). (4) Combining the endobiliary biopsy results, SEMS tissues, and CA 19–9 levels yielded the best diagnostic accuracy, with an AUC of 0.90 (0.83–0.98). Detection of biliary obstruction using the combination strategy was better than the diagnostic results based on biopsy alone according to recent 3-year data. Our study suggested that SEMS removal could help establish a diagnosis of suspected malignant biliary obstruction.

Comparison of colonic stenting and stoma creation as palliative treatment for incurable malignant colonic obstruction.

Background and AimSelf‐expandable metal stent (SEMS) is a favorable therapeutic option for patients with incurable malignant colonic obstruction (MCO). However, their long‐term efficacy and safety compared with those of stoma creation have not been well investigated. This study aimed to compare these long‐term outcomes between these two techniques in patients with incurable MCO.MethodsThis retrospective cohort included patients with incurable MCO with SEMS insertion (n = 105) and stoma creation (n = 97) between January 2009 and December 2019. The primary outcomes were patency after the procedure and 1‐year re‐intervention rates.ResultsThe patency of the SEMS group was lower than that of the stoma group (88.9 vs 93.2% at 6 months, 84.1 vs 90.5% at 12 months, and 65.8 vs 90.5% at 18 months; log‐rank test, P = 0.024), but 1‐year re‐intervention rates were not different between the groups (10 vs 8%, P = 0.558). The median patency durations were 190 days for SEMS insertion and 231 days for stoma creation. Majority (84%) of SEMS patients did not require any re‐intervention until death. The early complication rate did not differ between the groups (P = 0.377), but SEMS insertion had fewer late minor complications than stoma creation (5 vs 22%, P = 0.001).ConclusionSEMS insertion is a safe and effective treatment for patients with incurable MCO. Although SEMS insertion had a lower patency than stoma creation, especially after 1 year, the 1‐year re‐intervention rates were not different, and SEMS durability was sufficient in most patients.

Post-tuberculosis tracheobronchial stenosis: long-term follow-up after self-expandable metallic stents placement and development of a prediction score—the Restenosis Score

BackgroundThe insertion of self-expandable metallic stents (SEMS) for post-tuberculosis tracheobronchial stenosis (PTTS) was controversial. This study aimed to evaluate the efficacy and safety of SEMS for treating PTTS, and developed a scoring system for predicting the occurrence of restenosis after stenting in PTTS patients.MethodsWe conducted a retrospective review of 87 patients who were diagnosed with PTTS and experienced SEMS insertion between January 2000 and December 2017. All procedures were performed via flexible bronchoscopy under conscious sedation and local anesthesia.ResultsA total of 85 SEMS were successfully placed in 77 patients. Comparing with pre-stenting, there were significant improvements in the lumen diameters of the stenotic segment, mMRC scale and lung function after short-term SEMS placement. During the long-term (average 163.32 months) follow-up, 48 patients (62.3%) did not develop restenosis after stenting; the other 29 patients (37.7%) developed and eventually, 12 remained under interventional therapies and 11 had bronchial atresia. Multivariate Cox regression analysis revealed that the difference value between SEMS length and the stenosis-segment length, stenosis type, and the number of pre-stenting thermal ablation were independently related to restenosis occurrence and were subsequently used to establish the Restenosis Score. The model’s development group (0.83, 95% CI 0.74–0.92) and external validation set (0.94, 95% CI 0.77–1.00) showed excellent discrimination.ConclusionSEMS placement could serve as a safe and effective treatment option for most patients with PTTS. Further, we built a prediction model depending on the independent predictors of restenosis occurrence, the Restenosis Score. This validated tool might provide a decision support and a better management for PTTS patients who underwent SEMS implantation.

Esophageal carcinoma with tracheobronchoesophageal fistula due to esophageal stent, and self-expanding metallic stent insertion.

Esophageal carcinoma with tracheobronchoesophageal fistula due to esophageal stent, and self-expanding metallic stent insertion.

Impact of endobiliary radiofrequency ablation on biliary drainage in patients with malignant biliary strictures treated with uncovered self-expandable metal stents: a randomized controlled multicenter trial

Endobiliary radiofrequency ablation (RFA), usually combined with endoscopic stent insertion, is a simple procedure with the potential to improve stent patency and patient survival for malignant biliary obstruction. We conducted this randomized multicenter trial to evaluate the impact of RFA on stent patency. Eighty-six patients with malignant biliary obstruction and nonresectable tumors (pancreatic carcinoma, cholangiocarcinoma, or metastases) were included and randomly assigned to receive a self-expandable metal stent (SEMS) only (n= 44) or RFA followed by SEMS insertion (RFA+SEMS, n= 42). The primary outcome measure was stent patency after 3 and 6 months; secondary outcome measures were patient survival and early adverse events within 30 days. Technical success rates for RFA and stent insertion were 100% and 98.8%, respectively. Stent patency after 3 and 6 months did not differ significantly between groups (RFA+SEMS group, 73.1% and 33.3%, respectively; SEMS-only group, 81.8% and 52.4%, respectively; P= .6). Similarly, the addition of RFA did not impact overall survival (hazard ratio, .72; P= .389 for RFA+SEMS). The adverse event rate in the RFA+SEMS group was 10.5% compared with 2.3% in the SEMS-only group, without a statistically significant difference (P= .18). RFA as an addition to SEMS implantation had no positive impact on patency rate or survival. (Clinical trial registration number: DRKS00018993.).

Angle of covered self-expandable metallic stents after placement is a risk factor for recurrent biliary obstruction.

BACKGROUNDStudies have shown that covered self-expandable metallic stents (CSEMS) with a low axial forces after placement can cause early recurrent biliary obstruction (RBO) due to precipitating sludge formation. AIMTo ascertain whether the angle of CSEMS after placement is a risk factor for RBO in unresectable distal malignant biliary obstruction (MBO).METHODSBetween January 2010 and March 2019, 261 consecutive patients underwent self-expandable metallic stent insertion by endoscopic retrograde cholangiopancreatography at our facility, and 87 patients were included in this study. We evaluated the risk factors for RBO, including the angle of CSEMS after placement as the primary outcome. We measured the obtuse angle of CSEMS after placement on an abdominal radiograph using the SYNAPSE PACS system. We also evaluated technical and functional success, adverse events, time to RBO (TRBO), non-RBO rate, survival time, cause of RBO, and reintervention procedure as secondary outcomes.RESULTSWe divided the patients into two cohorts based on the presence or absence of RBO. The angle of CSEMS after placement (per 1° and per 10°) was evaluated using the multivariate Cox proportional hazard analysis, which was an independent risk factor for RBO in unresectable distal MBO [hazard ratio, 0.97 and 0.71; 95% confidence interval (CI): 0.94-0.99 and 0.54-0.92; P = 0.01 and 0.01, respectively]. For early diagnosis of RBO, the cut-off value of the angle of CSEMS after placement using the receiver operating characteristic curve was 130° [sensitivity, 50.0%; specificity 85.5%; area under the curve 0.70 (95%CI: 0.57-0.84)]. TRBO in the < 130° angle group was significantly shorter than that in the ≥ 130° angle group (P < 0.01).CONCLUSIONThis study suggests that the angle of the CSEMS after placement for unresectable distal MBO is a risk factor for RBO. These novel results provide pertinent information for future stent management.

Laparoscopic resection after self-expanding stent insertion for obstructive left-sided colorectal cancer: Clinicopathological features and outcomes

Laparoscopic resection for obstructive colon cancer (CC) after insertion of self-expanding metallic stents (SEMSs) is reportedly difficult. However, this has not yet been thoroughly investigated. Therefore, we investigated the influence of SEMS insertion on laparoscopic resection. This retrospective comparative study included 87 patients with obstructive left-sided CC (December 2011-December 2019). Patients were assigned to two groups based on elective laparoscopic surgery for (1) obstructive CC necessitating emergent decompression with SEMS insertion (SEMS group) and (2) obstructive CC without emergent decompression (control group). The SEMS group had a longer operation time (283.3 ± 79.3 min vs 222.2 ± 79.4 min, P = 0.002) and greater blood loss (204.8 ± 417.6 mL vs 53.7 ± 166.1 mL, P = 0.029) on univariate analysis; however, in multiple linear regression analysis, SEMS was not an independent risk factor for both operation time (Δ operation time 25.5 min: P = 0.19) and blood loss (Δ blood loss 33.6 mL: P = 0.58). The complication rate based on Clavien-Dindo grade II did not differ significantly (17% vs 20%, P = 1.00), whereas the rates of conversion to laparotomy (17% vs 2%, P = 0.016) and stoma creation (26% vs 2%, P = 0.001) were higher in the SEMS group. In oncological outcomes, there was no intergroup difference in the 5-year disease-free survival (80.0% vs 72.2%, P = 0.76) and overall survival (100% vs 86.3%, P = 0.25). Laparoscopic surgery after SEMS for left-sided CC is demanding due to higher conversion rates to open surgery. However, this study also revealed that it is as safe as laparoscopic surgery for cases without SEMS because of comparable complication rate and long-term outcomes.

Preoperative diagnosis of obstructive colitis in colorectal cancer patients who underwent self-expandable metallic stent insertion as a bridge to surgery

PurposeObstructive colitis (OC) is a risk factor of anastomotic leakage in colorectal cancer resection. We aimed to clarify the relationship between the severity of OC and clinicopathological findings and to detect predictive factors of OC. MethodsWe retrospectively reviewed 43 cases of colectomy after self-expandable metallic stent placement for left-sided colorectal cancer. Preoperative diagnosis of OC was made by multiple modalities (initial computed tomography (CT), presurgical CT, and colonoscopy). We classified OC macroscopically in resected specimens into five groups (Grade 0: none, 1: mild [mild edema], 2: moderate [severe edema, redness, erosion], 3: severe [ulceration, bleeding], 4: very severe [necrosis, perforation]), and investigated the relationship between the preoperative assessment, surgical findings and the severity of OC. ResultsOC of Grade 2 or more (53.5%) was significantly correlated with severe edema in initial CT. There was no significant correlation between OC and anastomosis rate. The creation of covering stoma was significantly higher in the Grade 2 or more OC group. No leakage was observed in either group. ConclusionsInitial CT may be most useful for prediction of OC. It is important to make a preoperative diagnosis of OC by combining multiple modalities, which enables to determine the appropriate location for resection, anastomosis, and construction of a covering stoma.