Malignant gastric outlet obstructions: treatment by means of coaxial placement of uncovered and covered expandable nitinol stents

Management of Malignant Gastric Outlet Obstruction: A Comprehensive Review on the Old, the Classic and the Innovative Approaches

Gastrojejunostomy is the principal method of palliation for unresectable malignant gastric outlet obstructions (GOO). Gastrojejunostomy was traditionally performed as a surgical procedure with an open approach butrecently, notable progress in the development of minimally invasive procedures such as laparoscopic gastrojejunostomies have emerged. Additionally, advancements in endoscopic techniques, including endoscopic stenting (ES) and endoscopic ultrasound-guided gastroenterostomy (EUS-GE), are becoming more prominent. ES involves the placement of self-expandable metal stents (SEMS) to restore luminal patency. ES is commonly the first choice for patients deemed unfit for surgery or at high surgical risk. However, although ES leads to rapid improvement of symptoms, it carries limitations like higher stent dysfunction rates and the need for frequent re-interventions. Recently, EUS-GE has emerged as a potential alternative, combining the minimally invasive nature of the endoscopic approach with the long-lasting effects of a gastrojejunostomy. Having reviewed the advantages and disadvantages of these different techniques, this article aims to provide a comprehensive review regarding the management of unresectable malignant GOO.

Malignant gastric outlet obstruction: Which is the best therapeutic option?

Malignant gastric outlet obstruction (MGOO) is a clinical condition characterized by the mechanical obstruction of the pylorus or the duodenum due to tumor compression/infiltration, with consequent reduction or impossibility of an adequate oral intake. MGOO is mainly secondary to advanced pancreatic or gastric cancers, and significantly impacts on patients' survival and quality of life. Patients suffering from this condition often present with intractable vomiting and severe malnutrition, which further compromise therapeutic chances. Currently, palliative strategies are based primarily on surgical gastrojejunostomy and endoscopic enteral stenting with self-expanding metal stents. Several studies have shown that surgical approach has the advantage of a more durable relief of symptoms and the need of fewer re-interventions, at the cost of higher procedure-related risks and longer hospital stay. On the other hand, enteral stenting provides rapid clinical improvement, but have the limit of higher stent dysfunction rate due to tumor ingrowth and a subsequent need of frequent re-interventions. Recently, a third way has come from interventional endoscopic ultrasound, through the development of endoscopic ultrasound-guided gastroenterostomy technique with lumen-apposing metal stent. This new technique may ideally encompass the minimal invasiveness of an endoscopic procedure and the long-lasting effect of the surgical gastrojejunostomy, and brought encouraging results so far, even if prospective comparative trial are still lacking. In this Review, we described technical aspects and clinical outcomes of the above-cited therapeutic approaches, and discussed the open questions about the current management of MGOO.

Covered Metal Stent after Dysfunction of Uncovered Stents for Palliation of Gastrointestinal Malignant Obstruction

Background

Self-expanding metal stents (SEMS) have been used for the palliative treatment of malignant gastrointestinal tract obstruction. However, restenosis or incomplete expansion of a first stent is a frequent complication, and the effectiveness of reintervention with placement of a second stent is still controversial.

Objective

To evaluate the clinical outcomes of covered SEMS (cSEMS) placement after dysfunction of uncovered SEMS (uSEMS) by the stent-in-stent technique.

Patients and Methods

We retrospectively studied a consecutive series of patients receiving palliative treatment for malignant gastrointestinal obstruction with cSEMS placement after uSEMS dysfunction in a tertiary center from January 2013 to August 2018. Technical and clinical success, time of patency, and adverse events were analyzed.

Results

Twelve patients were included; their mean age was 60 ± 9 years. Eleven patients had gastric outlet obstruction, and 1 patient had compression of the transverse colon due to gastric neoplasia. In 5 cases, there was absence of early clinical success with uSEMS and stent dysfunction in 7 cases (median patency time: 81 days). There was 100% technical success and 91.7% clinical success after cSEMS placement. There were no adverse events nor need for reintervention. The median patency time after placement of both stents was 163 days (vs. 71 days with the initial stent).

Conclusion

cSEMS placement after uSEMS dysfunction is technically feasible and a clinically effective treatment for patients with recurrent malignant gastrointestinal obstruction, with good stent patency in the medium/long term. This approach seems to be safe and without increase in adverse effects.

Malignant gastric outlet obstruction: Which is the best therapeutic option?

Malignant gastric outlet obstruction (MGOO) is a clinical condition characterized by the mechanical obstruction of the pylorus or the duodenum due to tumor compression/infiltration, with consequent reduction or impossibility of an adequate oral intake. MGOO is mainly secondary to advanced pancreatic or gastric cancers, and significantly impacts on patients’ survival and quality of life. Patients suffering from this condition often present with intractable vomiting and severe malnutrition, which further compromise therapeutic chances. Currently, palliative strategies are based primarily on surgical gastrojejunostomy and endoscopic enteral stenting with self-expanding metal stents. Several studies have shown that surgical approach has the advantage of a more durable relief of symptoms and the need of fewer re-interventions, at the cost of higher procedure-related risks and longer hospital stay. On the other hand, enteral stenting provides rapid clinical improvement, but have the limit of higher stent dysfunction rate due to tumor ingrowth and a subsequent need of frequent re-interventions. Recently, a third way has come from interventional endoscopic ultrasound, through the development of endoscopic ultrasound-guided gastroenterostomy technique with lumen-apposing metal stent. This new technique may ideally encompass the minimal invasiveness of an endoscopic procedure and the long-lasting effect of the surgical gastrojejunostomy, and brought encouraging results so far, even if prospective comparative trial are still lacking. In this Review, we described technical aspects and clinical outcomes of the above-cited therapeutic approaches, and discussed the open questions about the current management of MGOO.

Effect of the type of electrical stimulation on spinal fusion in a rat posterolateral spinal fusion model

BACKGROUND CONTEXT

Posterolateral fusion (PLF) with autogenous iliac bone graft is one of the most common surgical procedures for lumbar spinal disease. However, its limited success demands new biologically competent graft enhancers or substitutes. Although the use of direct current (DC) electrical stimulation has been shown to increase rate of successful spinal fusions, little is known about the effect of the type of current in DC stimulation.

PURPOSE

To evaluate the effects of various DC stimulators on the strength and success rate of posterolateral fusion facilitated by using a nitinol mesh container, in rats.

STUDY DESIGN

This was an experimental animal study.

METHODS

A conductive, tubular nitinol mesh container was used to carry small pieces of bone grafts. The nitinol mesh container received electrical stimulation via a lead that connected the container to different types of DC stimulators. Sixty male Sprague-Dawley rats were divided into three groups (N=20 in each): a control group that underwent PLF with a nitinol container filled with autograft, a constant DC group that received a nitinol container and constant DC (100 μA), and a pulsed DC group that received a nitinol container and pulsed DC (100 μA, 100 Hz, 200 μs). The rats underwent PLF between L4 and L5, and transverse processes were grafted with bilateral iliac grafts. A stimulator was implanted subcutaneously. The rats were sacrificed 8 weeks postsurgery, and lumbar spines were removed. Spinal fusion was evaluated by microcomputed tomography, manual testing, biomechanical testing, histologic examination, and molecular analysis.

RESULTS

All animals in the DC stimulation groups displayed solid fusion, whereas only 70% of control animals showed solid fusion. Radiographic images, biomechanical testing, histologic examination, and molecular analysis revealed improved fusion in the order control group<constant DC group<pulsed DC group. The volume of new bone mass was significantly higher in the pulsed DC group (p<.05). Fusion was more solid in the pulsed DC group than in control group (p<.05). The pulsed DC group displayed the lowest inflammatory responses.

CONCLUSIONS

Pulsed DC electrical stimulation is efficacious in improving both strength and fusion rate in a rat spinal fusion model. In addition, tubular nitinol mesh, made of conductive suture, appears useful for holding small pieces of bone grafts and maintaining a good environment for bone fusion.

CLINICAL RELEVANCE

Pulsed DC electrical stimulation may be potentially useful to increase the fusion rate after spinal fusion in humans. Future research is required to evaluate the safety and efficacy of tubular nitinol mesh and pulsed DC electrical stimulation in humans.

Winged Partially Covered Self-Expandable Metal Stent to Prevent Distal Migration in Malignant Gastric Outlet Obstruction

BACKGROUND

Through-the-scope implantation of self-expandable metal stents can be used for the palliation of malignant gastric outlet obstruction. Although covered stents were developed to prevent tumor ingrowth, often seen with uncovered stents, migration is still a major problem. Especially, surgical treatment is required for some patients if distal migration occurs.

AIMS

To evaluate the usefulness of the newly designed winged stent that was developed to prevent distal stent migration.

METHODS

This was a single-center, single-arm, retrospective study. A total of 63 inoperable cancer patients with symptomatic gastric outlet obstruction were reviewed to evaluate the safety and efficacy of a newly designed partially covered self-expandable metal stent with star-shaped wing flaps at the proximal end to reduce distal stent migration.

RESULTS

Technical and clinical successes were achieved in 100% and 87.3% of patients, respectively. The gastric outlet obstruction scoring system score significantly improved after stent placement (from median 1 to 2, P < 0.001). The median duration of stent patency was 147 days (interquartile range 76-201), and median duration of overall survival was 176 days (interquartile range 79-325). Stent migration was observed in seven patients (11.1%), and restenosis was developed in 12 patients (19.0%). All cases of migration were proximal, and no distal migration was observed. Endoscopic removal of migrated stents was performed successfully in all cases.

CONCLUSIONS

The newly designed winged stent showed feasible efficacy and safety for malignant gastric outlet obstruction. Furthermore, it effectively prevented distal stent migration.

Comparison on the Efficacy between Partially Covered Self-Expandable Metal Stent with Funnel-Shaped Enlarged Head versus Uncovered Self-Expandable Metal Stent for Palliation of Gastric Outlet Obstruction

Background

Shape modification has been one of the methods adopted to improve stent patency but has not always translated into positive outcome. The aim of this study was to compare the efficacy of shape-modified partially covered self-expandable metal stent (SEMS) that has enlarged head versus uncovered SEMS for palliation of gastric outlet obstruction (GOO).

Methods

A total of 48 patients underwent insertion of either enlarged-head SEMS (n = 24) or uncovered SEMS (uSEMS) (n = 24) for palliation of GOO from July 2009 to July 2016. Patients with inoperable or advanced malignancy were included. Technical feasibility and clinical outcomes were compared.

Results

Technical success rate was 100% (24/24) and 95.8% (23/24) for enlarged-head SEMS group and uSEMS group, respectively. Clinical success rate was 87.5% (21/24) and 87.0% (20/23) for enlarged-head SEMS group and uSEMS group, respectively. The gastric outlet obstruction scoring system score significantly improved in both groups (p < 0.001 for both). Mean survival was similar between the groups: enlarged-head SEMS group, 99.3 days (range, 19–358 days) versus uSEMS group, 82.1 days (range, 11–231 days) (p = 0.418). The mean stent patency also showed no difference between the groups: enlarged-head SEMS group, 87.1 days (range, 8–358 days) versus uSEMS group, 60.4 days (range, 2–231 days) (p = 0.204). With enlarged-head SEMS, distal migration did not occur, but proximal migration was observed in four cases.

Conclusions

Distal migration was prevented by shaping the SEMS to have an enlarged head, but improvement in stent patency could not be observed.

Covered versus uncovered metal stents for malignant gastric outlet obstruction: Systematic review and meta-analysis

BACKGROUND AND AIM

Self-expandable metal stents (SEMS) are used for non-resectable malignant gastric outlet obstruction (GOO). Studies of covered versus uncovered SEMS have yielded inconsistent results as a result of heterogeneity in design and patient population. We carried out a meta-analysis to compare covered and uncovered gastroduodenal SEMS.

METHODS

Using MEDLINE, Embase, and the Cochrane database, we identified 1624 patients from 13 prospective and retrospective studies that evaluated covered and uncovered SEMS for malignant GOO and were published until October 2016. We pooled data on SEMS dysfunction, technical and clinical success, and adverse events using the fixed-effect or random-effects model.

RESULTS

Compared with uncovered SEMS, covered SEMS did not show any significant difference in stent dysfunction risk (risk ratio [RR], 1.02; 95% confidence interval [CI], 0.79-1.32). A subgroup analysis of five randomized trials suggested a trend toward a lower dysfunction risk in covered SEMS (RR, 0.63; 95% CI, 0.45-0.88). Covered SEMS were associated with a lower occlusion risk (RR, 0.44; 95% CI, 0.28-0.68), but with a higher migration risk (RR, 4.28; 95% CI, 2.89-6.34). Technical and clinical success rates were comparable between the groups. Overall adverse events tended to be more frequent in covered SEMS (RR, 1.75; 95% CI, 1.09-2.83).

CONCLUSIONS

Outcomes of covered and uncovered gastroduodenal SEMS were comparable, although the lower dysfunction rate of covered SEMS observed in the analysis of randomized trials needs further investigation. Antimigration mechanisms for covered SEMS and identification of patients who can achieve longer patency from uncovered SEMS would help improve the outcomes of gastroduodenal SEMS.

Safety and efficacy of palliative colorectal stent placement using a nasal endoscope technique

The purpose of this study was to evaluate the safety and efficacy of palliative self-expanding metallic stent (SEMS) placement using a nasal endoscope technique in the context of colorectal malignant obstruction. Eighteen patients with malignant colorectal obstruction who underwent palliative SEMS insertion using a nasal endoscope technique at the Toyonaka Municipal Hospital from August 2005 to August 2011 were enrolled and retrospectively analyzed. In all cases, a guidewire could be inserted on the oral side of the tumor. The placement success rate was 94.4% (17/18), and the complication rate was 23.5% (4 cases). The stent migrated in 3 cases, and perforation occurred in 1 case following bevacizumab chemotherapy. These outcomes indicate that stenting is useful for terminal patients and that nasal endoscopy is useful in cases of difficult guidewire placement.

Bioreducible polymer-delivered siRNA targeting MMP-9: suppression of granulation tissue formation after bare metallic stent placement in a rat urethral model

PURPOSE

To evaluate the effectiveness of small interfering RNA (siRNA) targeting matrix metalloproteinase 9 (MMP-9) in suppressing granulation tissue formation caused by bare metallic stent placement in a rat urethral model.

MATERIALS AND METHODS

All experiments were approved by the committee of animal research. In 20 Sprague-Dawley male rats (weight range, 300-350 g), a self-expanding metallic bare stent was inserted in the urethra with fluoroscopic guidance. One group of 10 rats (group A) was treated with MMP-9 siRNA/bioreducible branched polyethylenimine-disulfide cross-linked-indocyanine green (bioreducible BPEI-SS-ICG), while the other group of 10 rats (group B) received control siRNA/bioreducible BPEI-SS-ICG treatment. All rats were sacrificed at 4 weeks. The therapeutic effectiveness of the MMP-9 siRNA/bioreducible BPEI-SS-ICG complex was assessed by comparing the two results of retrograde urethrography, histologic examination, and quantification of MMP-9 by using zymography and Western blot analysis between the two groups. The Mann-Whitney U test was used to evaluate differences.

RESULTS

Stent placement was successful in all rats without a single case of migration at follow-up. Retrograde urethrography performed 4 weeks after stent placement demonstrated significantly larger luminal diameters of the urethra within the stents in group A compared with those in group B (P = .011). Histologic analysis revealed that the mean percentage of granulation tissue area (P < .001), mean number of epithelial layers (P < .001), and mean thickness of submucosal fibrosis (P < .001) were significantly decreased in group A compared with group B. Meanwhile, the mean density of inflammatory cell infiltration did not significantly differ between the two groups (P = .184). Quantitative analysis disclosed MMP-9 levels to be lower in group A relative to group B, indicating positive inhibition of MMP-9 by MMP-9 siRNA/bioreducible BPEI-SS-ICG.

CONCLUSION

MMP-9 siRNA/bioreducible BPEI-SS-ICG is effective for inhibiting granulation tissue formation after bare metallic stent placement in a rat urethral model.

Percutaneous transhepatic treatment using retrievable covered stents in patients with benign biliary strictures: mid-term outcomes in 68 patients

BACKGROUND

Percutaneous balloon dilation of benign biliary stricture has been the most widely used alternative to endoscopic treatment; however, the rate of recurrence has varied from 15 to 44 %. Recently, several investigators have reported that percutaneous transhepatic placement of retrievable covered stents is feasible for the treatment of benign biliary strictures. However, these studies had only a small number of patients and had short follow-up periods.

AIM

The purpose of this study was to investigate the mid-term outcomes of a retrievable covered stent for treatment of benign biliary strictures.

METHODS

We retrospectively assessed 68 patients who underwent percutaneous transhepatic placement and removal of a retrievable covered stent between March 2007 and November 2012, for treatment of benign biliary strictures. Forty-two patients had not previously undergone interventional treatment, whereas 26 had recurrent or refractory strictures despite previous percutaneous procedures.

RESULTS

Placement of the retrievable covered stents was technically successful in all patients. Stent migration occurred in 11 (16.2 %) patients. The mean indwelling period of drainage catheter and stent were 5.8 months (range, 3-22.5 months) and 3 months (range, 2-6.5 months), respectively. Clinical success was achieved in 59 (86.8 %) patients. During the mean follow-up of 36 months (range, 8.5-65 months), 12 (20 %) of 60 patients had recurrence of clinically significant strictures. The primary patency rates at 1, 2, 3, 4, and 5 years were 91, 89, 76, 68, and 68 %, respectively.

CONCLUSION

Mid-term outcomes suggested that percutaneous treatment of benign biliary strictures using a retrievable covered stent was a clinically effective method.

Additional gastroduodenal stent placement: retrospective evaluation of 68 consecutive patients with malignant gastroduodenal obstruction

BACKGROUND

Self-expandable metallic stent placement is widely used to manage malignant gastroduodenal obstructions. However, the techniques and effectiveness of additional gastroduodenal stent placement have not been evaluated until now.

PURPOSE

To evaluate the technical feasibility, clinical effectiveness, and complications of additional gastroduodenal stent placement in patients with recurrent obstructive symptoms after primary gastroduodenal stenting.

MATERIAL AND METHODS

We retrospectively analyzed data from 68 consecutive patients who had additional gastroduodenal stents placed for recurrent obstruction. Clinical effectiveness was assessed using technical and clinical success rates, gastric outlet obstruction score improvement after primary and additional stent placement, and complications.

RESULTS

Additional stent placement was technically successful in 66 of the 68 patients (97%) and symptomatic improvement was achieved in 58 (85%). The gastric outlet obstruction score improved after primary stent placement (0.3 to 1.4) and additional stent placement (0.2 to 1.4). Complications occurred in 12 of 68 patients (18%) and were caused by tumor overgrowth (n = 7), stent collapse (n = 2), food impaction (n = 1), jaundice (n = 1), and duodenal perforation (n = 1).

CONCLUSION

Additional gastroduodenal stent placement is technically feasible and clinically effective for patients with recurrent gastric outlet obstruction after stent placement.

Comparison of uncovered and covered stents for the treatment of malignant duodenal obstruction caused by pancreaticobiliary cancer

BACKGROUND

Few clinical studies to date have compared different types of self-expandable metallic stents (SEMS) and their outcomes in patients with pure duodenal obstruction caused by pancreaticobiliary cancer. The aim of this study was to compare the clinical effectiveness and side effects of uncovered and covered SEMS for the palliation of duodenal obstruction caused by pancreaticobiliary cancer.

METHODS

We retrospectively analyzed all patients with pancreaticobiliary cancer who underwent upper endoscopy with SEMS placement for malignant duodenal obstruction at the National Cancer Center of Korea between April 2003 and December 2010. The technical and clinical success rates of the procedure, complications, and durations of stent patency and overall survival were evaluated.

RESULTS

We identified 70 patients with a mean age of 51.2 years (range = 39-81 years); of these, 46 (65.7 %) had pancreatic cancer, 9 (12.9 %) had bile duct cancer, 11 (15.7 %) had gallbladder cancer, and 4 (5.7 %) had cancer of the ampulla of Vater. Twenty-four patients (34.3 %) received covered SEMSs and 46 (65.7 %) received uncovered SEMSs. Technical and clinical success rates were similar for the covered and uncovered stent groups. The complication rate was higher in the covered than in the uncovered group (62.5 vs. 34.8 %, P = 0.025), due primarily to a significantly higher stent migration rate (20.8 vs. 0 %, P = 0.004). Perforation as a late complication occurred in four patients, two in each group (8.3 vs. 4.3 %, P = 0.425). Stent patency tended to be shorter for covered than for uncovered duodenal stents (13.7 ± 8.6 weeks vs. not reached, P = 0.069).

CONCLUSIONS

The use of uncovered stents may be a preferred option for duodenal obstruction secondary to pancreaticobiliary malignancies, since they were effective in preventing stent migration and tended to have longer patency than covered stents. Careful attention should be paid to signs and symptoms of perforation during follow-up.

Self-expandable metallic stent placement in the palliative treatment of malignant obstruction of gastric outlet and duodenum

Background/Aims

To asses the usefulness of flexible metallic stents in the palliation of malignant obstruction of gastric outlet and duodenum.

Methods

Retrospective review was performed between January 2006 and December 2011 in 30 patients. Thirty consecutive patients with obstruction of the gastric outlet underwent palliative treatment with self-expandable flexible metallic stents. Complications and clinical outcomes were assessed.

Results

Twenty-four patients had advanced gastric carcinoma at the antrum and/or pylorus, four patients had obstruction at the pylorus due to pancreas tumours and one patient had duodedum and one patient had gall bladder tumour. Symptoms improved in 82.7% of the patients after the procedure. The improvement in ability to eat using the score system was statistically significant (p<0.001). Tumor ingrowth and/or overgrowth were seen in four patients (13.3%), and a second stent was inserted in these patients. The mean stent patency was 100 days (range, 5 to 410). The mean survival was 120.76±38.96 days.

Conclusions

Endoscopic placement of self-expendable metallic stents under fluoroscopy is a safe and effective treatment for the palliation of patients with inoperable malignant gastric outlet obstruction caused by stomach or pancreas cancer.

Tumor overgrowth after expandable metallic stent placement: experience in 583 patients with malignant gastroduodenal obstruction

OBJECTIVE

The objective of our study was to assess the incidence, predictive factors, and treatment of tumor overgrowth after placement of expandable metallic dual stents in patients with malignant gastroduodenal obstruction.

MATERIALS AND METHODS

Expandable metallic dual stents were inserted under fluoroscopic guidance in 583 patients with symptomatic malignant gastroduodenal obstruction. We retrospectively reviewed prospectively collected patient records to determine the incidence and treatment of tumor overgrowth after stent placement and used multivariate analysis to determine factors predicting tumor overgrowth.

RESULTS

Tumor overgrowth occurred after stent placement in 22 of 583 patients (3.8%) (range, 41-634 days; mean, 179.0 days). Duodenal lesions (odds ratio [OR], 4.505; p = 0.002), longer survival time (OR, 1.003; p = 0.001), and length of obstruction (OR, 0.783; p = 0.035) were independent predictors of tumor overgrowth. Twenty of the 22 patients were successfully treated by placement of a second dual stent, whereas the other two patients refused placement of a second stent or other further treatment. Overall, 19 of 20 patients (95%) showed improvement in symptoms after second stent placement. Duodenal perforation occurred in one of the 20 patients 125 days after placement of a second stent and was treated surgically.

CONCLUSION

Tumor overgrowth seems to be an uncommon complication of expandable metallic dual stent placement in patients with malignant gastroduodenal obstruction. Tumor overgrowth is associated with duodenal lesions, longer survival time, and shorter stricture length. Tumor overgrowth can be successfully managed by coaxial insertion of a second dual-expandable metallic stent into the obstructed first stent.

Fully covered, retrievable self-expanding metal stents (Niti-S) in palliation of malignant dysphagia: long-term results of a prospective study

BACKGROUND

In the palliative treatment of malignant dysphagia, fully covered, retrievable metal stents are not commonly used, mainly due to the high risk of migration. Therefore, we performed a prospective study to evaluate the clinical efficacy of a fully covered, retrievable self-expanding metal stent (Niti-S).

METHOD

Between October 1998 and February 2009, 100 consecutive patients with malignant esophageal obstruction treated with the fully covered Niti-S stent (Niti-S, Taewoong Medical, Seoul, South Korea) were included. Data collected contained functional outcome, feasibility of endoscopic stent retrieval, recurrent dysphagia, complications, and survival.

RESULT

At 4 weeks after stent placement, dysphagia significantly improved in all patients (p = 0.000). Recurrent dysphagia occurred in 19 of 100 patients treated with Niti-S stents (19%) mainly due to tumor overgrowth (7/100, 7%), stent migration (6/100, 6%), and food impaction (6/100, 6%). Endoscopic stent retrieval was successful in all the attempted 17 patients (17/100, 17%)--7 overgrowth, 6 stent migration, 2 stent degradation, and 2 severe pain. Major complications were 2 hemorrhage, 2 severe pain, and 1 tracheal compression (5/100, 5%), and minor complications were 10 retrosternal pain and 7 symptomatic gastroesophageal reflux (17/100, 17%). After a median follow-up of 142 days, 97 patients had expired. There was no stent-related mortality or 30-day mortality.

CONCLUSION

The fully covered, retrievable Niti-S stent has proved its effectiveness for palliation of malignant dysphagia and feasibility of endoscopic retrieval. We estimate its dog-bone shaped flanges at both ends and it being completely covered provide good resistance to migration and overgrowth.

Malignant gastroduodenal obstruction: retrospective comparison of endoscopic and surgical palliative therapy

INTRODUCTION

Endoscopic stenting (ES) is a minimally invasive alternative to surgical gastroenterostomy (GE) for palliation of malignant gastroduodenal obstructions. This consecutive, retrospective analysis compares the clinical outcome of all patients undergoing ES or GE in the same period.

METHODS

ES was performed at the Endoscopy Department, University Hospital Mannheim or at the Interdisciplinary Endoscopy Department, University Hospital Hamburg-Eppendorf. GE was performed at the Surgical Department, University Hospital Mannheim. All palliative ES or GE on patients with malignant gastroduodenal obstruction without earlier gastric resections between January 2001 and April 2007 were evaluated. Main outcome measurements were ability of solid food intake (gastric outlet obstruction score), persistence of nausea and vomiting (gut function score), length of hospital stay, morbidity, mortality and re-interventions.

RESULTS

A total of 44 ES and 43 GE were performed. Nausea and vomiting--measured by means of the gut function score--persisted in significantly more patients in the GE group than in those who underwent stent placement (p = 0.0102). The gastric outlet obstruction score at discharge from the hospital revealed no significant difference in the ability of solid food intake between the groups. The hospital stay was significantly longer in the GE group (p = 0.0003). There was no significant difference in mortality and the rates of complications and re-interventions.

CONCLUSION

In this study, ES is a generally equivalent--and in several points superior--alternative to GE for palliation of malignant gastroduodenal obstruction. ES seems to be the less invasive alternative for symptomatic patients. GE has good results in patients with longer survival and can be practiced within abdominal explorations.

Severity of initial stent angulation predicts reintervention after successful palliative enteral stenting for malignant luminal obstruction

BACKGROUND AND AIM

Recurrent stent obstruction necessitating reintervention is problematic and incompletely understood. The aim of the present study was to identify factor(s) predisposing to reintervention.

METHODS

Retrospective review of patients (n = 117) referred to a single major endoscopic referral centre for palliative enteral stenting from 1999 to 2006. Twelve were excluded due to inadequate follow-up data (n = 7) or initial radiographic documentation (n = 5). A total of 105 patients (gastroduodenal n = 57, colonic n = 48) were therefore analyzed. The primary outcome of interest was recurrent obstruction necessitating reintervention. Kaplan-Meier analysis of potential factors predisposing to reintervention, including stent angulation (mild [<15°], moderate [15°-90°], severe [>90°]) was completed for 98 patients (technically successful enteral stenting).

RESULTS

Technical and clinical success were achieved in 98 of 105 (93.3%) and 92 of 98 (93.9%) cases, respectively. Post-stenting median survival was 97.5 days (range 3-1054). Eighteen patients (18.4%) required reintervention for stent obstruction at a median time to reintervention of 85 days (range 7-481). Increased stent angulation (severe vs mild hazard ratio 6.73 (95% confidence interval 1.59-27.59), P = 0.009) was the only statistically significant factor in multivariate analysis predicting reintervention.

CONCLUSIONS

Despite its limitation as a retrospective review, this study found that reintervention for stent obstruction is necessary in almost one in five cases, and increasing severity of stent angulation is the most important risk factor.

Endoscopic stent placement for stenosis of the digestive tract: an analysis of 273 cases

AIM: To assess the safety, efficacy and patient satisfaction of endoscopic stent placement for stenosis of the digestive tract.

METHODS: A total of 273 patients with stenosis of the digestive tract were included in the study, of whom 242 had esophageal and cardial stenosis, 24 had gastroduodenal stenosis, 7 had colorectal stenosis; 256 had malignant stenosis, 17 had benign stenosis; 273 had gastrointestinal obstruction symptoms; 15 suffered from esophageal fistula. Endoscopic placement of stents was performed in all patients. The safety, efficacy and patient satisfaction were evaluated after stent placement.

RESULTS: Stents were successfully placed in all patients (100%). Gastrointestinal obstruction symptoms were alleviated in 266 patients (97.4%). Esophageal fistula was successfully closed in 15 patients (100%). Stent-related adverse effects occurred in 156 patients (57.1%), mainly including chest (abdominal) pain in 87 cases (31.9%) and bleeding in 39 cases. Only one patient with malignant esophageal stenosis died of gastrointestinal bleeding after esophageal stent placement. Re-stenosis was detected in 43 patients (15.8%). Approximately 93.8% of patients were satisfied with the treatment.

CONCLUSION: Endoscopic stent placement is an effective and relatively safe treatment for stenosis of the digestive tract and esophageal fistula. The rate of treatment satisfaction is high.

Malignant gastric outlet obstructions: treatment with self-expandable metallic stents

Unresectable malignant gastric outlet obstruction (GOO) severely affects the quality of life, with complications that include nausea, vomiting, aspiration, pain, and malnutrition. Although palliative surgical procedures have been traditionally performed, they are associated with high morbidity and mortality rates. Placing self-expandable metallic stents is associated with higher clinical success rates, lower morbidity, shorter time from the procedure to starting oral intake, lower incidence of delayed gastric emptying, and a shorter hospital stay than palliative surgery. Fluoroscopic or endoscopic placement of either bare or covered self-expandable metallic stents is a safe, nonsurgical, palliative treatment option for unresectable malignant GOOs, with a high clinical success rate and a low rate of serious complications. Stent obstruction and migration are the most common complications, but most can be managed by interventional treatments. Although there have been substantial developments in stent design over the past decade, large prospective, randomized studies are required to determine the ideal stent for malignant GOOs.

Stenting of the upper gastrointestinal tract: current status

Minimally invasive image-guided insertion of self-expanding metal stents in the upper gastrointestinal tract is the current treatment of choice for palliation of malignant esophageal or gastroduodenal outlet obstructions. A concise review is presented of contemporary stenting practice of the upper gastrointestinal tract, and the procedures in terms of appropriate patient evaluation, indications, and contraindications for treatment are analyzed, along with available stent designs, procedural steps, clinical outcomes, inadvertent complications, and future technology. Latest developments include biodegradable polymeric stents for benign disease and radioactive or drug-eluting stents for malignant obstructions.

Palliative treatment of malignant gastric outlet obstructions with a large-diameter metallic stent: prospective preliminary study

Large-diameter (24 mm) stent placement was prospectively performed in seven patients with mild malignant gastric outlet obstruction (ie, allowing passage of adult endoscope) or unusual obstruction location. The degree of dysphagia was categorized into five grades: 0 (regular diet), 1 (some solid food), 2 (soft diet), 3 (liquid diet), and 4 (complete dysphagia). One month after stent placement, all patients had improvement of at least one grade in their level of dysphagia. Large-diameter stent placement may be clinically effective in gastric outlet obstruction cases with a high risk of stent migration as a result of mild obstructions or unusual obstruction location.

Palliative treatment of malignant gastroduodenal obstruction with metallic stent: prospective comparison of covered and uncovered stents

BACKGROUND

The placement of self-expandable metallic stents (SEMS) is known to be effective palliative treatment of malignant gastroduodenal obstruction. There are two types of SEMS--covered and uncovered--each with its own advantages and disadvantages. This study was conducted to compare between the clinical outcomes of covered and uncovered stents in patients with malignant gastroduodenal obstruction.

PATIENTS AND METHODS

The study was conducted prospectively from January 1998 to June 2007 and 154 patients were included. All had symptomatic gastroduodenal obstruction and were not candidates for curative operation. Seventy patients received covered SEMS, while the other 84 received uncovered SEMS. We compared technical and clinical success rates, tumour ingrowth rate, stent migration rate, stent patency time and patient survival in both SEMS groups.

RESULTS

The technical and clinical success rates of the covered and uncovered stent groups did not differ. Stent migration was more frequent in the covered stent group than in the uncovered group (17.1% versus 0%; p=0.0001). Tumour ingrowth was more frequent in the uncovered stent group than in the covered group (16.6% versus 2.9%; p=0.0066). Stent re-intervention rate, stent patency time and patient survival did not differ between groups.

CONCLUSION

Covered and uncovered stent insertions are technically feasible and effective palliative treatment of malignant gastroduodenal obstruction. Covered stents can reduce the risk of tumour ingrowth, whereas uncovered stents are effective in preventing stent migration. However, covered stents did not differ from uncovered stents in regard to other clinical outcomes.

Treatment of malignant gastric outlet obstruction with endoscopically placed self-expandable metal stents

Malignant gastroduodenal obstruction can occur in up to 20% of patients with primary pancreatic, gastric or duodenal carcinomas. Presenting symptoms include nausea, vomiting, abdominal distention, pain and decreased oral intake which can lead to dehydration, malnutrition, and poor quality of life. Endoscopic stent placement has become the primary therapeutic modality because it is safe, minimally invasive, and a cost-effective option for palliation. Stents can be successfully deployed in the majority of patients. Stent placement appears to lead to a shorter time to symptomatic improvement, shorter time to resumption of an oral diet, and shorter hospital stays as compared with surgical options. Recurrence of the obstructive symptoms resulting from stent occlusion, due to tumor ingrowth or overgrowth, can be successfully treated with repeat endoscopic stent placement in the majority of the cases. Both endoscopic stenting and surgical bypass are considered palliative treatments and, to date, no improvement in survival with either modality has been demonstrated. A tailored therapeutic approach, taking into consideration patient preferences and involving a multidisciplinary team including the therapeutic endoscopist, surgeon, medical oncologist, radiation therapist, and interventional radiologist, should be considered in all cases.

Metallic stent placement in the palliative treatment of malignant gastric outlet obstructions: primary gastric carcinoma versus pancreatic carcinoma

OBJECTIVE

The objective of our study was to compare the clinical effectiveness of metallic stent placement for relief of gastric outlet obstruction caused by gastric carcinoma and pancreatic carcinoma.

MATERIALS AND METHODS

A total of 207 patients with gastric outlet obstruction caused by inoperable gastric carcinoma (n = 147) or pancreatic carcinoma (n = 60) underwent metallic stent placement.

RESULTS

Technical success of metallic stent placement was achieved in all patients. Clinical success was achieved in 97% and 93% of patients with gastric and pancreatic carcinoma, respectively (p = 0.286). The overall complication rate did not differ significantly between the gastric (29%) and pancreatic (23%) carcinoma groups (p = 0.441). Stent collapse was significantly more frequent in the gastric carcinoma group (11%) than the pancreatic carcinoma group (2%) (p = 0.027), whereas serious complications, including gastrointestinal bleeding and intestinal perforation, occurred more frequently in the pancreatic (7%) than the gastric (1%) carcinoma group (p = 0.026). The cumulative survival period was significantly longer in the gastric carcinoma (median, 153 days) than the pancreatic carcinoma (median, 90 days) group (p = 0.041), but cumulative stent patency did not differ significantly between the gastric carcinoma (median, 350 days) and pancreatic carcinoma (median, 385 days) groups (p = 0.415).

CONCLUSION

Metallic stent placement was clinically effective in the palliative treatment of gastric outlet obstruction in patients with gastric and pancreatic carcinoma. The two groups differed significantly in the rates of stent collapse and serious complications and patient survival after stent placement.

Treatment of malignant gastric outlet obstruction with stents: an evaluation of the reported variables for clinical outcome

Background

Malignant gastric outlet obstruction (GOO) is commonly seen in patients with advanced gastric-, pancreatic-, duodenal, hepatobiliary or metastatic malignancies. Ten to 25% of patients with pancreatic cancer will develop duodenal obstruction during the course of the disease. Duodenal stenting with self-expandable metal stents is an alternative treatment to surgical bypass procedures. Our aim was to review the published literature regarding treatment of malignant GOO with stents to reveal whether the information provided is sufficient to evaluate the clinical effects of this treatment

Methods

A literature search from 2000 – 2007 was conducted in Pub Med, Embase, and Cochrane library, combining the following search terms: duodenal stent, malignant duodenal obstruction, gastric outlet obstruction, SEMS, and gastroenteroanastomosis.

All publications presenting data with ≥ 15 patients and only articles written in English were included and a review focusing on the following parameters were conducted: 1) The use of graded scoring systems evaluating clinical success; 2) Assessment of Quality of life (QoL) before and after treatment; 3) Information on stent-patency; 4) The use of objective criteria to evaluate the stent effect.

Results

41 original papers in English were found; no RCT's. 16 out of 41 studies used some sort of graded scoring system. No studies had objectively evaluated QoL before or after stent treatment, using standardized QoL-questionnaires, 32/41 studies reported on stent patency and 9/41 performed an oral contrast examination after stent placement. Objective quantitative tests of gastric emptying had not been performed.

Conclusion

Available reports do not provide sufficient relevant information of the clinical outcome of duodenal stenting. In future studies, these relevant issues should be addressed to allow improved evaluation of the effect of stent treatment.

Covered expandable nitinol stents for malignant gastroduodenal obstructions

BACKGROUND AND AIM

The aim of the present study was to investigate the clinical effectiveness, safety, and outcome associated with the use of covered expandable Nitinol stents (Taewoong Medical, Seoul, Korea) for the treatment of malignant gastroduodenal obstructions.

METHODS

Between March 2001 and October 2004, covered expandable Nitinol stents were placed in 68 consecutive patients under endoscopic and fluoroscopic guidance for the following reasons: gastric carcinoma (n = 49), recurrent carcinoma after partial gastrectomy (n = 7), or another malignant neoplasm involving the duodenum (n = 12).

RESULTS

Technical success was achieved in 60 of the 68 patients (88.2%). After stent placement, mean dysphagia score improved from a mean of 3.5 to 1.2 (P < 0.001). The mean period of primary stent patency was 107.2 days. During follow up (mean 4.4 months; range, 1-15 months), major complications (migration [6], bleeding [3], perforation [1], ingrowth [1], overgrowth [7], fistula [1]) occurred in 19 patients (27.9%), and stent migration occurred in six (8.8%) (proximal migration into the stomach [n = 3], or distal migration [n = 3]). Recurrent dysphagia (mainly due to tumor ingrowth/overgrowth) occurred in eight patients (11.8%).

CONCLUSION

Covered expandable Nitinol stents appear to offer an effective and feasible palliative therapy in patients with a malignant gastroduodenal obstruction.

Endoscopic stenting-Where are we now and where can we go?

Self expanding metal stents (SEMS) play an important role in the management of malignant obstructing lesions in the gastrointestinal tract. Traditionally, they have been used for palliation in malignant gastric outlet and colonic obstruction and esophageal malignancy. The development of the polyflex stent, which is a removable self expanding plastic stent, allows temporary stent insertion for benign esophageal disease and possibly for patients undergoing neoadjuvant chemotherapy prior to esophagectomy. Potential complications of SEMS insertion include perforation, tumour overgrowth or ingrowth, and stent migration. Newer stents are being developed with the aim of increasing technical and clinical success rates, while reducing complication rates. Other areas of development include biodegradable stents for benign disease and radioactive or drug-eluting stents for malignant disease. It is hoped that, in the future, newer stents will improve our management of these difficult conditions and, possibly, provide prognostic as well as symptomatic benefit in the setting of malignant obstruction.

Membrane degradation of covered stents in the upper gastrointestinal tract: frequency and clinical significance

PURPOSE

To evaluate the frequency, clinical significance, and predictive factors of membrane degradation of covered stents in the upper gastrointestinal (UGI) tract.

MATERIALS AND METHODS

From 1996 to 2006, 166 stents were removed from 151 patients. Indications for stent removal included temporary stent placement for esophageal cancer before radiation therapy or radiation-chemotherapy (n = 53), stent migration (n = 40), temporary stent placement for a benign UGI stricture (n = 32), pain (n = 21), recurrent obstruction (n = 16), incomplete stent expansion (n = 1), recurrent transesophageal fistula (n = 2), and aspiration (n = 1). Removed stents were examined to evaluate possible causes of membrane degradation. Multivariate analysis was performed to determine the predictive factors of membrane degradation.

RESULTS

Degradation of the covering membrane occurred in 14 of the 166 stents (8%). Recurrent obstruction due to tumor ingrowth (n = 7) and reopening of the transesophageal fistula (n = 1) through the degraded membrane occurred in eight stents (5%). At multivariate logistic regression analysis, the type of covering membrane (P = .018), stricture location (P = .006), and duration of stent placement (P = .002) were significantly associated with degradation of the covering membrane.

CONCLUSIONS

Degradation of the covering membrane after stent placement in the UGI tract is not an uncommon event, and recurrent obstruction or fistula can occur through the degraded membrane. A polyurethane membrane is not biostable and dissolves over time, particularly in the gastroduodenal area.

Metallic stent placement in patients with recurrent cancer after gastrojejunostomy

PURPOSE

To assess the technical feasibility and clinical effectiveness of placement of expandable metallic stents in patients with recurrent cancer after a gastrojejunostomy.

MATERIALS AND METHODS

Data from 39 consecutive patients who had undergone metallic stent placement for recurrent malignant obstruction after a gastrojejunostomy were retrospectively analyzed. Thirty patients underwent a distal gastrectomy with a gastrojejunostomy with (n=10) or without (n=20) jejunojejunostomy, two patients underwent distal gastrectomy with a Roux-en-Y gastrojejunostomy, and seven patients underwent a palliative gastrojejunostomy with (n=5) or without (n=2) jejunojejunostomy. A total of 57 metallic stents were used in this study: four bare stents, 29 partially covered stents, and 24 fully covered stents. Types of obstruction were classified into 12 patterns and types of stent placement were classified into 16 patterns.

RESULTS

Stent placement was technically successful in all patients. After stent placement, 35 of the 39 patients (90%) experienced improvement of their symptoms, two showed no change, and the remaining two showed aggravation of symptoms as a result of faulty stent placement. Two patients treated with stent placement only in the afferent loop died of aspiration pneumonia. In one of two patients who underwent stent placement according to pattern 6, afferent loop syndrome occurred 10 days after stent placement and was treated by percutaneous pigtail catheter drainage. Stent migration occurred in four of 24 fully covered stents, but in none of the bare or partially covered stents. Tumor ingrowth occurred in one of four bare stents, tumor overgrowth in one of 29 partially covered stents, and mucosal prolapse in one of 24 fully covered stents; all were treated with a second stent placement.

CONCLUSIONS

Placement of expandable metallic stents in patients with recurrent cancer after a gastrojejunostomy seems to be feasible and effective, but accurate knowledge of the type of surgical procedure performed and determination of the pattern of tumor recurrence are important for successful stent placement.

Self-expanding metallic stents for gastric outlet obstruction resulting from stomach cancer: a preliminary study with a newly designed double-layered pyloric stent

BACKGROUND

Although endoscopic stent placement is now generally accepted as a palliative treatment for gastric outlet obstruction resulting from gastric cancer, it carries potential limitations such as tumor ingrowth or migration.

OBJECTIVE

Our purpose was to evaluate the technical and clinical efficacy of endoscopic placement of a newly designed double-layered combination pyloric stent.

DESIGN

Prospective, uncontrolled, single-center.

SETTING

Tertiary referral university hospital.

PATIENTS

Eleven patients with gastric outlet obstruction by unresectable stomach cancer.

INTERVENTIONS

Eleven patients received a double-layered combination pyloric stent (an outer uncovered stent to reduce migration and an inner polytetrafluoroethylene-covered stent to prevent tumor ingrowth).

MAIN OUTCOME MEASUREMENT

To evaluate technical success, clinical success, and complications, especially tumor ingrowth and migration.

RESULTS

Technical success was achieved in 11 of 11 (100%) patients. Among 11 patients in whom endoscopic stenting was placed successfully, clinical success was 90.9%, tumor ingrowth 0%, migration 9.1%, and tumor overgrowth 9.1%. Median stent patency period was 121 days.

LIMITATIONS

Small number of patients, uncontrolled study, short-term follow-up period.

CONCLUSIONS

We have described a technique for endoscopic metal stent placement by using the newly designed double-layered combination stent for gastric outlet obstruction by stomach cancer. This stent seems to be effective and looks promising for technical efficacy, clinical outcome, and preventing tumor ingrowth and migration.

Palliative nonvascular interventions

Interventional radiologists are often called on to help with quality of life issues in end-stage cancer patients. Many times, the discomfort can be directly associated to the tumor mass itself, but in other instances, tumors can cause secondary obstruction of normal structures that can lead to patient distress. As with most palliative care patients, their medical conditions are not conducive to major surgery; therefore minimally invasive techniques are ideal for the treatment of these conditions. The following discussion addresses the various nonvascular interventions available to these patients, including the indications and limitations of these procedures.

Treatment of gastric outlet and duodenal obstructions with uncovered expandable metal stents

AIM: To investigate and evaluate the technical feasibility and clinical effectiveness of fluoroscopically guided peroral uncovered expandable metal stent placement to treat gastric outlet and duodenal obstructions.

METHODS: Fifteen consecutive patients underwent peroral placement of Wallstent^TM Enteral Endoprosthesis to treat gastric outlet and duodenal obstructions (14 malignant, 1 benign). All procedures were completed under fluoroscopic guidance without endoscopic assistance. Follow-up was completed until the patients died or were lost, and the clinical outcomes were analyzed.

RESULTS: The technique success rate was 100%, and the oral intake was maintained in 12 of 14 patients varying from 7 d to 270 d. Two patients remained unable to resume oral intake, although their stents were proven to be patent with the barium study. One patient with acute necrotizing pancreatitis underwent enteral stenting to treat intestinal obstruction, and nausea and vomiting disappeared. Ten patients died during the follow-up period, and their mean oral intake time was 50 d. No procedure-related complications occurred. Stent migration to the gastric antrum occurred in one patient 1 year after the procedure, a tumor grew at the proximal end of the stent in another patient 38 d post-stent insertion.

CONCLUSION: Fluoroscopically guided peroral metal stent implantation is a safe and effective method to treat malignant gastrointestinal obstructions, and complications can be ignored based on our short-term study. Indications for this procedure should be discreetly considered because a few patients may not benefit from gastrointestinal insertion, but some benign gastrointestinal obstructions can be treated using this procedure.

Metallic stent placement in the palliative treatment of malignant gastroduodenal obstructions: prospective evaluation of results and factors influencing outcome in 213 patients

BACKGROUND

Metallic stents are a therapeutic option for patients with malignant GI obstruction.

OBJECTIVE

Our purpose was to evaluate the clinical effectiveness of a self-expandable metallic stent in 213 patients with malignant gastroduodenal obstruction and to identify prognostic factors associated with clinical outcomes.

DESIGN

Prospective cohort study.

SETTING

Single tertiary referral university hospital.

PATIENTS

Two hundred thirteen consecutive patients with symptomatic malignant gastric outlet or duodenal obstruction from 2001 to 2005.

INTERVENTIONS

Placement of a self-expandable metallic stent.

MAIN OUTCOME MEASUREMENTS

Prospective data collection focused on technical and clinical success, complications, and prognostic factors associated with stent patency.

RESULTS

Technical and clinical success were achieved in 94% and 94% of the patients, respectively, and the complication rate was 21%. The median and mean survival periods were 99 (95% CI, 78-121) and 159 days (95% CI, 116-203). The median and mean stent patency periods were 270 (95% CI, 234-413) and 324 days (95% CI, 128-412). With use of the multivariate Cox proportional hazard model, chemotherapy after stent placement (odds ratio, 0.19; 95% CI, 0.08-0.46; P < .001) was significantly associated with an increase in the maintenance of stent patency.

LIMITATIONS

Single-center experience and the lack of a control group.

CONCLUSIONS

Placement of a self-expandable metallic stent is clinically effective in patients with unresectable gastric outlet or duodenal obstruction. Chemotherapy after stent placement, albeit associated with increased migration rates, is associated with an increase in the maintenance of stent patency.

Anastomotic Recurrence of Gastric Cancer after Total Gastrectomy with Esophagojejunostomy: Palliation with Covered Expandable Metallic Stents

PURPOSE

To assess the technical feasibility, safety, and clinical effectiveness of the placement of expandable metallic stents in patients with anastomotic recurrence of gastric cancer after total gastrectomy with esophagojejunostomy.

MATERIALS AND METHODS

The authors retrospectively analyzed data from 32 patients in whom metallic stents were placed for recurrent obstruction after total gastrectomy with esophagojejunostomy. Technical and clinical success and complications with related interventions were evaluated. Overall survival and stent patency rates were calculated according to the Kaplan-Meier method.

RESULTS

Stent placement was technically successful in 30 of the 32 patients (94%). After stent placement, 29 patients (91%) experienced improvement of their symptoms. Fourteen complications occurred after stent placement, and these consisted of pain (n = 5, 16%), stent migration (n = 3, 9%), stent obstruction due to tumor overgrowth (n = 4, 13%), and abutment of the tortuous jejunal wall by the end of the stent (n = 2, 6%). In one of five patients with pain, the stent was removed 4 hours after placement because the pain could not be controlled with analgesics. The median survival and stent patency period were 87.0 and 140.0 days, respectively.

CONCLUSION

Placement of covered metallic stents in patients with anastomotic recurrence of gastric cancer after total gastrectomy with esophagojejunostomy is technically feasible, safe, and clinically effective.

Stent collapse as a delayed complication of placement of a covered gastroduodenal stent

OBJECTIVE

The purpose of this study was retrospective evaluation of the incidence, predictive factors, and interventional management of stent collapse after placement of a covered metallic stent in patients with obstruction of the gastric outlet or duodenum due to malignant disease.

MATERIALS AND METHODS

Among 259 patients with symptomatic malignant gastroduodenal obstruction successfully treated with stent placement, stent collapse occurred in 12 (4.6%) of the patients 34-270 days (mean, 101.8 days) after stent placement. Multivariate analysis was performed to evaluate factors predictive of stent collapse. Interventional management of stent collapse also was evaluated.

RESULTS

Multivariate analysis showed that presence of the stent in the peripyloric region (odds ratio, 27.745; p = 0.036), longer survival time (odds ratio, 1.016; p < 0.001), and absence of chemotherapy after stent placement (odds ratio, 31.661; p = 0.048) were independent predictors of stent collapse. Eleven patients with stent collapse were successfully treated with placement of a second bare stent. The twelfth patient refused further treatment.

CONCLUSION

Stent collapse is an uncommon delayed complication of placement of covered metallic stents in patients with malignant gastroduodenal obstruction. Collapse occurs most commonly in the peripyloric region, in patients with longer survival times, and in patients who do not undergo chemotherapy after stent placement. Stent collapse can be managed by coaxial placement of a second bare stent into the collapsed stent.

Stent versus gastrojejunostomy for the palliation of gastric outlet obstruction: a systematic review

BACKGROUND

Gastrojejunostomy (GJJ) is the most commonly used palliative treatment modality for malignant gastric outlet obstruction. Recently, stent placement has been introduced as an alternative treatment. We reviewed the available literature on stent placement and GJJ for gastric outlet obstruction, with regard to medical effects and costs.

METHODS

A systematic review of the literature was performed by searching PubMed for the period January 1996 and January 2006. A total of 44 publications on GJJ and stents was identified and reported results on medical effects and costs were pooled and evaluated. Results from randomized and comparative studies were used for calculating odds ratios (OR) to compare differences between the two treatment modalities.

RESULTS

In 2 randomized trials, stent placement was compared with GJJ (with 27 and 18 patients in each trial). In 6 comparative studies, stent placement was compared with GJJ. Thirty-six series evaluated either stent placement or GJJ. A total of 1046 patients received a duodenal stent and 297 patients underwent GJJ. No differences between stent placement and gastrojejunostomy were found in technical success (96% vs. 100%), early and late major complications 7% vs. 6% and 18% vs. 17%, respectively) and persisting symptoms (8% vs. 9%). Initial clinical success was higher after stent placement (89% vs. 72%). Minor complications were less frequently seen after stent placement in the patient series (9% vs. 33%), however the pooled analysis showed no differences (OR: 0.75, p = 0.8). Recurrent obstructive symptoms were more common after stent placement (18% vs. 1%). Hospital stay was prolonged after GJJ compared to stent placement (13 days vs. 7 days). The mean survival was 105 days after stent placement and 164 days after GJJ.

CONCLUSION

These results suggest that stent placement may be associated with more favorable results in patients with a relatively short life expectancy, while GJJ is preferable in patients with a more prolonged prognosis. The paucity of evidence from large randomized trials may however have influenced the results and therefore a trial of sufficient size is needed to determine which palliative treatment modality is optimal in (sub)groups of patients with malignant gastric outlet obstruction.

Endoscopic stenting in patients with recurrent malignant obstruction after gastric surgery: uncovered versus simultaneously deployed uncovered and covered (double) self-expandable metal stents

BACKGROUND

Uncovered, rather than covered, metal stents are commonly used for palliation of malignant gastric outlet obstruction because of the low risk of stent migration, but tumor ingrowth risk is a major drawback. Few reports address malignant obstruction after gastric surgery.

OBJECTIVE

Our purpose was to compare the technical feasibility and clinical outcome of using an endoscopic uncovered self-expandable metal stent (SEMS) and simultaneous use of uncovered and covered SEMS (double SEMS) in patients with recurrent malignant obstruction after gastric surgery.

DESIGN

Retrospective study.

SETTING

Tertiary care, academic medical center, from August 2000 to June 2005.

PATIENTS

Twenty patients were included in the study. All patients had symptomatic obstruction with nausea, vomiting, and decreased oral intake.

INTERVENTION

Ten patients received uncovered SEMS; the other 10 received double SEMS.

MAIN OUTCOME MEASUREMENTS

To compare tumor ingrowth and stent patency between the uncovered and the double-SEMS groups.

RESULTS

Technical and clinical successes were 10 of 10 and 8 of 10, respectively, in the uncovered SEMS group and 10 of 10 and 10 of 10, respectively, in the double SEMS group. Six of 10 patients (60%) with uncovered SEMS had tumor ingrowth compared with 1 of 10 patients with double SEMS, P = .057. Five of 10 patients (50%) with uncovered SEMS had very early restenosis, but no patients had early restenosis in the double SEMS group, P = .033. Stent patency was a median of 21.5 days (range, 7-217 days) in the uncovered SEMS group and 150 days (range 29-263 days) in the double SEMS group, P = .037. Survival duration was 109.5 days (range 29-280 days) and 150 days (range 29-263 days), respectively.

LIMITATIONS

This was a small retrospective study.

CONCLUSION

Simultaneous double stent placement seems to be technically feasible and effective for palliative treatment of recurrent malignant obstruction after gastric surgery. Double stent placement is important in preventing tumor ingrowth, especially very early restenosis, and prolongs stent patency. We suggest that this procedure be considered rather than uncovered stent alone as the primary choice for palliation of obstruction in such patients.

Benign tracheobronchial strictures: long-term results and factors affecting airway patency after temporary stent placement

OBJECTIVE

The purpose of our study was to evaluate long-term results and identify factors affecting airway patency after temporary placement of a covered, retrievable nitinol stent for benign tracheobronchial strictures.

MATERIALS AND METHODS

Polyurethane or polytetrafluoroethylene (PTFE)-covered retrievable expandable nitinol stents were placed fluoroscopically in 24 patients with benign tracheobronchial strictures. Improvement in respiratory status and complications were evaluated. Maintained patency of airway after temporary stenting was calculated and compared between the 2- and 6-month stenting groups. Factors for maintained patency after temporary stenting were evaluated.

RESULTS

A total of 30 stents were successfully placed and well tolerated in 24 patients. Tissue hyperplasia, stent migration, and bronchial obstruction of the left upper lobe occurred in 36.7%, 13.3%, and 3.3% of patients, respectively. All stents were successfully removed electively either 2 (n = 12) or 6 (n = 12) months after placement or when complications occurred (n = 6). During the follow-up period (mean, 24 months), dyspnea recurred in 15 of the 24 patients. The 6-month stenting group showed a lower recurrence rate (41.7% vs 83.3%, p = 0.045) and a better mean maintained patency (39.7 +/- 7.8 vs 9.4 +/- 5.4 months, p = 0.001) than the 2-month stenting group. Multivariate analysis showed that duration of stent placement (p = 0.002) and the occurrence of tissue hyperplasia (p = 0.026) were associated with maintained patency after temporary stenting.

CONCLUSION

Temporary placement of a covered, retrievable, expandable nitinol stent may be a safe and effective treatment for benign tracheobronchial strictures during the period the stent is in place. A high symptomatic recurrence rate of 62.5% was found after stent removal. Shortterm placement of the stent and tissue hyperplasia were associated with decreased airway patency.

Percutaneous transhepatic placement of covered, self-expandable nitinol stent for the relief of afferent loop syndrome: report of two cases

The author reports successful outcomes after percutaneous transhepatic placement of covered, self-expandable nitinol stents in two patients who had afferent loop syndrome caused by recurrent gastric carcinoma. A 46-year-old woman and a 60-year-old man who had undergone subtotal gastrectomy and gastrojejunostomy (Billroth II) were both admitted with symptoms of afferent loop syndrome. In each patient, enhanced abdominal computed tomography showed marked dilation of the jejunal limb and intrahepatic bile ducts incident to recurrent gastric carcinoma. Percutaneous transhepatic biliary drainage was successfully performed, and a multi-sidehole drainage catheter was placed beyond the papilla of Vater. Successful palliation of the afferent loop obstruction was achieved by placing a covered, self-expandable nitinol stent through the transhepatic biliary drainage route. There were no procedure-related complications, and both patients showed clinical improvement.