A comparison study on physical properties of self-expandable esophageal metal stents

Esophageal metal stent for malignant obstruction after prior radiotherapy

The association between severe adverse events (SAEs) and prior radiotherapy or stent type remains controversial. Patients with esophageal or esophagogastric junctional cancer who underwent stent placement (2005–2019) were enrolled in this retrospective study conducted at a tertiary cancer institute in Japan. The exclusion criteria were follow-up period of < 1 month and insufficient data on stent type or cancer characteristics. We used Mann–Whitney’s U test for quantitative data and Fisher’s exact test for categorical data. Multivariate analysis was performed using a logistic regression model. 107 stents were placed. Low radial-force stents (L group) were used in 51 procedures and high radial-force stents (H group) in 56 procedures. SAEs developed after nine procedures, the median interval from stent placement being 6 days (range, 1–141 days). SAEs occurred more frequently in the H (14%: 8/56) than in the L group (2%: 1/51) (P = 0.03). In patients who had undergone prior radiotherapy, SAEs were more frequent in the H (36%: 4/11) than in the L group (0%: 0/13) (P = 0.03). Re-obstruction and migration occurred after 16 and three procedures, respectively; these rates did not differ significantly between groups (P = 0.59, P = 1, respectively). Low radial-force stents may reduce the risk of SAEs after esophageal stenting.

In Vitro Evaluation of Mechanical Properties of Segmented Esophageal Self-Expandable Metal Stents: Innovative Test Methods Are Needed

Background: Self-expanding metal stents (SEMSs) in different geometric shapes are well established treatment options in diseases of the esophagus. Mechanical properties and stent design may have an impact on patient comfort, migration rate, and removability. In this in vitro study, we evaluated mechanical properties of three segmented SEMSs (segSEMSs) for the esophagus with regard to distinct stent sections. Materials and Methods: Radial forces were measured using a testing method distinguishing between circumferential radial and local radial force. The center parts of the segSEMSs were measured for circumferential radial forces without being affected by the flared ends. Axial forces were measured at 20° bending. Results: Circumferential radial force measurements over the full stent length showed substantial differences against measurements of the center parts of the stents as the flared ends falsify test results by up to 53%. Although circumferential radial forces of the center parts were about the same (<10% variances) for all segSEMSs, local radial forces showed considerable differences of up to 26%. One segSEMS showed high axial forces, whereas the other two only needed half of the force (up to 53%) to be bent to 20°. Conclusion: Flared ends of segSEMSs have a substantial impact on radial force measurements and therefore alter test results, confirmed by our separated center part test of segSEMSs. Our innovative setup whereby we compressed the stent in an asymmetric manner (local radial force) and evaluated sections of stents separately, indeed revealed differences to circumferential measurements, leading to a more in-depth knowledge of stent characteristics.

Patient Outcomes After Stent Failure for the Treatment of Acute Esophageal Perforation

BACKGROUND

Esophageal stent placement for acute esophageal perforation has become part of the treatment algorithm for many thoracic surgery programs. Despite high success rates, there are patients for which stent placement is not successful. This investigation summarizes the outcomes of a relatively large group of such patients.

METHODS

Patients who underwent esophageal stent placement for an acute perforation but required conversion to another form of therapy were identified from a prospectively collected institutional database. Excluded were patients whose perforation was associated with a malignancy. Patient demographics, operative and nonoperative invasive procedures, morbidities, mortality, and 6-month follow-up after discharge were reviewed.

RESULTS

Between 2008 and 2015, 26 patients who failed to seal their esophageal leak after stent placement were identified. Eighteen (69%) of these patients required an operative repair with primary closure of the perforation. Four (15%) primary repairs had a persistent leak controlled with subsequent stent placement. Four (15%) patients required an esophagectomy with cervical esophagostomy. Three patients (11%), because of comorbid conditions, were referred for hospice care. One patient (3%) refused operative repair and developed a chronic fistula that resolved with subsequent stent placement.

CONCLUSIONS

Esophageal stent placement continues to be a safe and effective treatment for acute esophageal perforation. Patients whose perforation does not seal with initial stent placement can be treated with primary surgical repair or esophagectomy without increasing their morbidity or mortality or compromising their prognosis.

Optimal radial force and size for palliation in gastroesophageal adenocarcinoma: a comparative analysis of current stent technology

BACKGROUND

The optimal use of esophageal stents for malignant and benign esophageal strictures continues to be plagued with variability in pain tolerance, migration rates, and reflux-related symptoms. The aim of this study was to evaluate the differences in radial force exhibited by a variety of esophageal stents with respect to the patient's esophageal stricture.

METHODS

Radial force testing was performed on eight stents manufactured by four different companies using a hydraulic press and a 5000 N force gage. Radial force was measured using three different tests: transverse compression, circumferential compression, and a three-point bending test. Esophageal stricture composition and diameters were measured to assess maximum diameter, length, and proximal esophageal diameter among 15 patients prior to stenting.

RESULTS

There was a statistically significant difference in mean radial force for transverse compression tests at the middle (range 4.25-0.66 newtons/millimeter N/mm) and at the flange (range 3.32-0.48 N/mm). There were also statistical differences in mean radial force for circumferential test (ranged from 1.19 to 10.50 N/mm, p < 0.001) and the three-point bending test (range 0.08-0.28 N/mm, p < 0.001). In an evaluation of esophageal stricture diameters and lengths, the smallest median diameter of the stricture was 10 mm (range 5-16 mm) and the median proximal diameter normal esophagus was 25 mm (range 22-33 mm), which is currently outside of the range of stent diameters.

CONCLUSIONS

Tested stents demonstrated significant differences in radial force, which provides further clarification of stent pain and intolerance in certain patients, with either benign or malignant disease. Similarly, current stent diameters do not successfully exclude the proximal esophagus, which can lead to obstructive-type symptoms. Awareness of radial force, esophageal stricture composition, and proximal esophageal diameter must be known and understood for optimal stent tolerance.

Endoscopic management of esophageal leaks

Traditionally, gold standard treatment for an acute esophageal perforation has been operative repair. Over the past two decades, there has been a paradigm shift towards the use of esophageal stents. Recent advances in biomaterial allowed a new generation of stents to be manufactured that combined (I) a non-permeable covering; (II) radial force sufficient to occlude a transmural esophageal injury and (III) improved ease of removability. The amalgamation of these developments set the stage for utilizing esophageal stents as part of the management algorithm of an acute esophageal perforation. This provides a safe and less invasive treatment route in lieu of direct primary repair and its well-documented significant failure rate. Esophageal stent placement for failed operative repair or esophageal leaks also had the potential to minimize the need for esophageal resection and diversion. When included in a multimodality hybrid treatment protocol, esophageal stents can optimize healing success rates and minimize the risks of adverse complications. This review summarizes the modern history of esophageal stent use in the treatment of esophageal perforation as well as the evidenced based recommendations for the use of esophageal stent placement in the treatment of acute esophageal perforation.

History of the Use of Esophageal Stent in Management of Dysphagia and Its Improvement Over the Years

The art and science of using stents to treat dysphagia and seal fistula, leaks and perforations has been evolving. Lessons learnt from the deficiencies of previous models led to several improvements making stent deployment easier, and with some designs, it was also possible to remove the stents if needed. With these improvements, besides malignant dysphagia, newer indications for using stents emerged. Unfortunately, despite several decades of evolution, as yet, there is no perfect stent that "fits all." This article is an overview of how this evolution process happened and where we are currently with using stents to manage patients with dysphagia and with other esophageal disorders.

Experience with stent implantation in malignant esophageal strictures: analysis of 1185 consecutive cases

PURPOSE

The aim of this retrospective study was to analyze the experience in endoprosthesis implantation in cases of malignant esophageal strictures.

METHODS

A total of 1185 consecutive patients underwent endoprosthesis implantation: through open surgery in 42 cases and by endoscopy in 1143 cases.

RESULTS

Stent implantation was performed successfully in 61.2% of cases. Dysphagia was resolved temporarily in 6.2% and permanently in 93.5% of cases. The score of dysphagia decreased from 1.93 to 0.38. Complications were detected in 23.7% of patients, and 69.2% of cases were treated by endoscopy. Wound complications were seen in 21.9% of patients intubated through surgery. The mean survival time of patients with esophageal intubation was 5.4 months and that of patients not eligible for stent implantation was 3.3 months.

CONCLUSIONS

Stent implantation improves the quality of life and gives an opportunity for adjuvant oncological therapy. Evaluation of morphologic anomalies is of considerable importance for achieving success in treatment through implantation.

Stents for benign and malignant esophageal strictures

This paper presents commentaries on endotherapy for esophageal perforation/leaks; treatment of esophageal perforation; whether esophageal stents should be used for treating benign esophageal strictures; what determines the optimal stenting period in benign esophageal strictures/leaks; how to choose an esophageal stent; how a new fistula secondary to an esophageal stent should be treated; which strategy should be adopted when a fistula of a cervical anastomosis occurs; intralesional steroids for refractory esophageal strictures; balloon and bougie dilators for esophageal strictures and predictors of response to dilation; whether refractory strictures from different etiologies respond differently to endotherapy; surgical therapy of benign esophageal strictures; and whether stenoses following severe esophageal burns should be treated by esophageal resection or esophageal bypass.

What is the preferred shape for an esophageal stent flange?

AIM

Self-expandable metallic stents (SEMS) for the gastrointestinal tract have different types of flanges at either the oral end or both ends to prevent stent migration. The effect of flange shape on the properties of SEMS, to our knowledge, has not been evaluated. The aim of this study was to measure the strain that a SEMS imposes on the adjacent wall and the anti-migration force (AF) exerted by three stents, each with a different flange shape.

METHODS

Stents with one of three different flanges (flared, dumbbell, and barrel) were designed and then their strain and AF values were measured with apparatuses devised in our laboratory.

RESULTS

Although the average maximal strain values at the flange were similar (508.4 µm/m, 513.3 µm/m and 486.4 µm/m for flared, dumbbell and barrel, respectively), strain values for each position differed among the three different types of stents. Strain values for the flared shape increased toward the stent end, reaching the maximum value. Maximal strain values for the dumbbell and barrel shapes were observed near the flange's midpoint. Maximal AF values differed significantly according to flange shape. Thus, the median maximal AF values were 1.85 newton, 1.35 newton, and 1.13 newton, for barrel, dumbbell and flared shapes, respectively.

CONCLUSIONS

The performance of braided esophageal SEMS with barrel shaped flanges is superior to that of SEMS with dumbbell or flared flanges, based on the strain on the adjacent wall and the prevention of stent migration.

Mid-gut stents

PURPOSE OF REVIEW

Gastrointestinal stents offer a feasible, safe, cost effective, and minimally invasive method for reestablishing luminal patency. Previous clinical reports and systematic reviews have demonstrated the role of enteral stents in both the upper and lower gastrointestinal tract. Over the last two decades, the rapid development of deep enteroscopy in concert with the evolution of various stent devices/deployment mechanisms has enabled placement of enteral stents in the mid-gut; hence this has been increasingly reported. The present article focuses on stenting in the mid-gut, a relatively novel term, referring to the small bowel between the ampulla and the ileocecal valve.

RECENT FINDINGS

Mid-gut stenting is technically more difficult than stenting in the upper and lower gastrointestinal tract, and therefore requires particular expertise, restricting its widespread utility. In total, 86 reported cases involving mid-gut stent deployment, by either endoscopic approaches (80.2%) or percutaneous approaches (19.8%), have been published. Although limited, these results have demonstrated that mid-gut stenting is reliable, effective, and a minimally invasive method for palliating malignant obstruction, as well as sealing leaks and fistulae.

SUMMARY

This article reviews the current status of mid-gut stenting, including endoscopic technique. The article also speculates about the potential for future advances within this field.

Outcomes following oesophageal stent insertion for palliation of malignant strictures: A large single centre series

BACKGROUND

Self-expanding metal stents (SEMS) are an accepted intervention for malignant dysphagia. Stents vary in ease of insertion, removability, migration and occlusion rates. This series reports the complications, morbidity and mortality associated with several SEMS.

METHOD

A prospective database of patients undergoing fluoroscopic guided oesophageal stent insertion for malignancy between June 2001 and June 2009 was analysed. Patient demographics, intervention outcomes and tumour variables were correlated with stent failure and patient survival. Multivariate analysis was performed to evaluate predictors for stent failure.

RESULTS

Two hundred and seventy-three stents were deployed using nine different types of SEMS. The median Mellow-Pinkas dysphagia score significantly improved from 3 to 1 post-stent insertion (P < 0.001), with a technical success rate of 98%. Stent complications occurred in 95 (36%) patients [recurrent dysphagia n = 49 (19%), migration n = 24 and occlusion n = 25]. Multivariate analysis demonstrates that the covered Niti S stent fails significantly more than the double-layered Niti S stent (OR = 4, P < 0.005).

CONCLUSION

Oesophageal stent insertion provides good palliation for malignant dysphagia, however recurrent dysphagia remains a problem. This major complication occurs more frequently with covered Niti S stents than double-layered Niti S stents. This finding may aid the stent choice used in advanced oesophageal malignancy.

[Palliative management of malignant oesophageal strictures with endoprosthesis implantation -- 25 years experience]

OBJECTIVES

The aim of this study was to analyse the feasibility of the use of oesophageal endoprosthesis based on a large series of cases.

METHODS

2952 malignant oesophageal strictures managed between 1984 and 2009 were analysed. While surgical intubation was carried out in 42 patients, endoscopic implantation was feasible in 1143 cases. Patients not eligible for oesophageal stenting were treated with gastrostomy in 125, percutaneous endoscopic gastrostomy in 19, catheter jejunostomy in 9 and supportive therapy in 965 cases, respectively.

RESULTS

Endoprosthesis could have been inserted in 61.2% of the patients. Dysphagia was terminated temporarily in 6.2% and permanently in 93.5%. Complications were detected in 23.7% of the cases, which included stent migration, perforation, bleeding, airway obstruction, early unexpected death, aspiration, stent obstruction, tumor overgrowth, oesophago-respiratory fistula formation and neoformation, and reflux. Complications were treated endoscopically primarily (69.2%). Lethal complication rate was 2.1% (27 cases). Furthermore, complication rate of patients who underwent surgical stent insertion was 21.9%. Mean survival of patients with oesophageal intubation was 5.4 months, with nutritional support via gastrostomy, percutaneous endoscopic gastrostomy or jejunostomy 3.6 months and with supportive therapy alone 3.2 months.

CONCLUSIONS

Oesophageal endoprosthesis insertion is an effective method for the palliative management of malignant oesophageal strictures. Stent implantation improves survival as well as quality of life. Methods used for nutritional support decreases hungriness but do not influence survival.

Expandable stents for benign esophageal disease

Partially covered self-expandable esophageal stents have been associated with unacceptable complications when used for benign esophageal disorders. With the introduction of removable or potentially removable fully covered stents and biodegradable stents, interest in using expandable stents for benign indications has been revived. Although expandable stents can offer a minimally invasive alternative to surgery, they can be associated with serious complications; hence, this approach should be considered in carefully selected patients, preferably on a protocol basis.

Randomised comparison of the FerX Ella antireflux stent and the ultraflex stent: proton pump inhibitor combination for prevention of post-stent reflux in patients with esophageal carcinoma involving the esophago-gastric junction

BACKGROUND AND AIM

Metal stents placed across the gastroesophageal junction in patients with malignant dysphagia frequently present with reflux symptoms. We compared an antireflux stent with a standard open stent used in combination with proton pump inhibitor medication.

METHODS

Forty-nine patients with dysphagia due to inoperable carcinoma in the lower third of the esophagus were randomly selected to receive either a antireflux valve stent (FerX-Ella) (n = 22) or a covered standard open stent (Ultraflex), which was combined with proton pump inhibitors such as omeprazole (n = 26). The technical success, the presence of reflux, and complications were recorded.

RESULTS

Reflux was seen in 3/22 patients (13.6%) in the FerX-Ella group and in 2/26 patients (7.7%) in the Ultraflex and proton pump inhibitor combination group (P-value not significant). In both groups, a significant improvement in the dysphagia score was seen and no statistically significant difference was detected between the two groups (P = 0.84). The FerX-Ella stents migrated more frequently (32%) than the Ultraflex stents (23%). This also necessitated surgical intervention more frequently in the FerX-Ella group (2/22, 9.1%) compared to the Ultraflex group (1/26, 3.8%).

CONCLUSION

The antireflux stent had no demonstrable advantages compared to the combination of standard open stent and proton pump inhibitor medication.

Endoluminal insertion of colonic stents

For patients with obstructing colonic tumours endoluminal stents provide an alternative to surgical decompression. Used either as permanent palliation, or as a bridge to surgery, colonic stents have been shown to be effective, safe, and cost effective.

[Endoscopic treatment of squamous cell esophageal cancer]

OBJECTIVE

In this article, it was evaluated the role of endoscopic procedures for the management of squamous cell esophageal cancer.

DATA SOURCE

Relevant publications cited at PubMed database in the last 10 years were analyzed and compared with the experience developed at the Gastrointestinal Endoscopy Division of the Department of Gastroenterology of the University of São Paulo School of Medicine. Mucosectomy and advanced tumor tunnelization were the most important developments in that area.

DATA SYNTHESIS

Endoscopic mucosal resection of early epidermoid cancer of the esophagus is indicated when the lesion is confined to the epithelium (m1) or to the lamina propria (m2). The described 5-year survival rate after endoscopic mucosal resection of intramucosal epidermoid tumor of the esophagus approaches 95%. Based on the available evidence, it seems reasonable to indicate endoscopic mucosal resection as a first-choice treatment for patients with intramucosal epidermoid esophageal carcinoma. There are a variety of endoscopic palliative methods for dysphagia relief in advanced esophageal cancer.

CONCLUSIONS

The choice will vary according to the anatomical features and location of the tumor, patient preferences, local and expertise availability. The technical success rate for placement of metal stents across the malignant stenosis is close to 100%. The rate of long-term palliation of dysphagia approaches 80% which makes expandable metal stents the treatment of choice for palliation of obstructive symptoms caused by advanced squamous cell cancer of the esophagus.

Safety and efficacy of argon plasma coagulation trimming of malpositioned and migrated biliary metal stents: a controlled study in the porcine model

BACKGROUND

Argon plasma coagulation (APC) has been used to trim uncovered Elgiloy stents, but the extent of thermal damage and bile duct injury is not known. The goal of this study was to evaluate the safety and efficacy of APC for this application.

METHODS

Eight Elgiloy (covered and uncovered) and four nitinol stents were deployed in the bile duct at ERCP in 12 anesthetized pigs. In nine pigs, the excess distal ends were trimmed in vivo using short bursts of APC. Three pigs served as controls. Bile ducts and stent specimens were then harvested for gross and histological examinations by a single-blinded pathologist.

RESULTS

APC effectively trimmed all the stents. Seven APC-treated bile ducts and three controls showed epithelial distortion consistent with pressure injury from stent expansion. Two APC-treated bile ducts showed mild thermal injury. The damage was superficial, extending to a maximum depth of 0.1 mm with rare foci involving subepithelial connective tissue.

CONCLUSION

APC at indicated settings effectively cuts covered and uncovered Elgiloy as well as nitinol stents, but can cause biliary epithelial injury secondary to conduction of heat and electrical energy. Proper technique and settings should be followed and short bursts of energy judiciously applied in order to minimize this danger.

Endoscopic stenting of colonic tumours

Self-expandable metal stents (SEMS) are useful for the non-surgical relief of malignant colonic obstruction. They may be used both as a palliative measure and as a pre-operative bridge to facilitate a one-stage surgical resection of primary colonic tumours. SEMS may be placed endoscopically or by interventional radiologists without the use of endoscopy. In experienced centres SEMS can be successfully placed in approximately 90% of cases. Although it is known that the placement of these devices is feasible, there are no prospective trials comparing stent placement for colonic obstruction to routine surgical care. Additionally, there are no studies comparing the outcome of the method of placement (endoscopic versus radiological). This chapter reviews the types of expandable metal stent used for treatment of colonic obstruction, the indications for their insertion, their methods of insertion, and outcomes following insertion. Future research directions using expandable stents for colonic tumours are also addressed.

New approach to malignant strictures of the esophagus

Primary esophageal cancer is the most common cause of malignant esophageal stricture. Prognosis and treatment outcomes vary with the stage of the disease. Endoscopic ultrasound has a high accuracy rate for local and regional staging. Surgery is curative for early cancer. Endoscopic mucosal resection, photodynamic therapy, or brachytherapy can be used with curative intent for early cancer, especially in patients with comorbid conditions precluding surgery. Unfortunately, the majority of patients with esophageal cancer present with advanced disease. The primary aim in these patients is to alleviate symptoms with a minimum of side effects and reinterventions. Palliative surgery or chemoradiotherapy can be associated with high morbidity and mortality rates. Several endoscopic techniques for palliation are available, and all have the potential of significantly improving swallowing. The choice of a particular endoscopic approach is usually determined by local expertise and characteristics of the stricture.

Effectiveness of open versus antireflux stents for palliation of distal esophageal carcinoma and prevention of symptomatic gastroesophageal reflux

PURPOSE

To compare the effectiveness of an antireflux stent with that of a standard open stent in preventing symptoms of gastroesophageal reflux in patients with inoperable distal esophageal cancer.

MATERIALS AND METHODS

Fifty consecutive patients with inoperable distal esophageal tumors underwent placement of either a standard open or an antireflux stent across the cardia. Stents were allocated randomly before assessment of the stricture. All patients were followed up prospectively by the departmental research nurses. Technical and clinical success, reflux symptoms, complications, and reintervention rates were assessed. P values of observed differences were calculated by using the chi(2) and log-rank tests as appropriate.

RESULTS

The technical success rate was 100%. Improvement in dysphagia was identical in both groups (three points on a five-point scale). Twenty-four (96%) of 25 patients with standard open stents had symptoms of esophageal reflux; 19 (76%) of 25 required treatment. Three (12%) of 25 patients with antireflux stents reported esophageal reflux; one (4%) of 25 required treatment. This difference was significant (P <.001). There was no significant difference in survival, complications, or reintervention rate. One case of late esophageal perforation occurred in each group. One patient died of aspiration within 24 hours after insertion of a standard open stent; no procedure-related deaths occurred with the antireflux stent.

CONCLUSION

This antireflux stent is as safe and effective as the standard open stent in relieving malignant dysphagia and was successful in reducing symptomatic gastroesophageal reflux.

Endoscopic palliation of unresectable malignant oesophageal strictures with self-expanding metal stents: comparing Ultraflex and Esophacoil stents

BACKGROUND

Two types of self-expanding metal stents to palliate dysphagia in patients with unresectable malignant oesophageal strictures have been compared.

METHODS

From February 1996 to October 2000, 50 metal stents (23 covered Ultraflex and 27 Esophacoil) were placed in 50 patients (40 males, mean age: 67+/-12 years, range: 33-100, mean dysphagia score: 3.18+/-0.66) with unresectable malignant oesophageal strictures. Patients were followed until death. A retrospective review has been made of a prospectively collected database.

RESULTS

The two groups were comparable as far as concerns degree of dysphagia, location and stricture length. Stent placement was successful in all cases. Covered Ultraflex stent was placed in 2 patients with oesophagobronchial fistula. No procedure-related deaths were seen. Early severe complications occurred in 2 patients (perforation in 1 and tumour bleeding in 1, in the Esophacoil group). Nine patients and 1 patient complained of pain following Esophacoil and Ultraflex stent placement, respectively. Late complications were asymptomatic rupture of distal Esophacoil rings in 2 patients, symptomatic Ultraflex stent migration in 2 and tumour overgrowth in 3 (Esophacoil 1, Ultraflex 2). Mean dysphagia score at 4 weeks after stent placement was 1.9+/-0.77. Mean survival was 177+/-109 days (range: 35-603 days). There were no significant differences in technical success, dysphagia palliation, complications (except chest pain) and survival using the two types of stent.

CONCLUSIONS

Self-expanding metal stents are safe with high technical success and achieve satisfactory long-term palliation for dysphagia. The covered Ultraflex and Esophacoil stents are equally effective.

New approach to radial expansive force measurement of self expandable esophageal metal stents

The accurate measurement of radial expansive force is crucial for optimal design and implantation of self expandable esophageal metal stents. In the present study, a new method of measurement under experimental conditions simulating actual stent implantation has been developed. This method offers precise and reproducible measurements and can be applied to a wide variety of stent types. In particular, the method enables one to measure expansive pressure as well as the true radial expansive force up to the radial compression ratio of 72%, covering the range of compression often encountered in a partially obstructed lumen. The test results for various kinds of metal stents are presented and compared. Based on these results, three important points of observation critical in explaining and predicting the expansion characteristics of stents have been reported. Further understanding and characterization of these findings will be necessary for developing new stents with outstanding clinical efficacy.

The role of oesophageal stenting in the non-surgical management of oesophageal strictures

The role of oesophageal stenting continues to evolve, with several new stents currently on the market. These stents possess anti-reflux valves, internal plastic coatings and retrievable threads. In patients with malignant dysphagia, management should ideally take place within multi-disciplinary teams such that accurate tumour staging occurs prior to treatment. Multi-modality therapy can not only improve dysphagia and response rates but may also improve survival. Several non-surgical palliative techniques are available to recanalize malignant obstruction, including oesophageal stenting. Other therapeutic modalities include the use of endoluminal laser therapy, photodynamic therapy, argon beam and bipolar electrocoagulation, ethanol injection and intracavity brachytherapy. Their use often depends on local availability and expertise. Although the initial costs of metal stents are high, the overall costs compare favourably with other forms of palliative therapy that often require multiple procedures with repeated inpatient hospitalization. Treatment of refractory benign strictures with oesophageal stents remains uncommon and several recent reports using retrievable stents appear to improve outcome, although more work is required in this area.

Delayed complications after esophageal stent placement for treatment of malignant esophageal obstructions and esophagorespiratory fistulas

PURPOSE

To evaluate delayed complications after esophageal expandable metallic stent placement.

MATERIALS AND METHODS

From April 1993 to December 1997, 90 expandable metallic stents were placed in 82 consecutive patients with inoperable malignant esophageal obstruction (n = 49) or malignant esophagorespiratory fistula (n = 33). Stents used included covered Gianturco-Rosch Z stents (n = 20), Wallstents (covered, n = 31; uncovered, n = 13), and Ultraflex stents (covered, n = 8; uncovered, n = 10). Patients were followed prospectively and monitored for delayed complications, defined as major (hemorrhage, tracheal compression, stent migration, perforation or fistula formation, granulomatous obstruction, tumor ingrowth and overgrowth, funnel phenomenon, and stent covering disruption) or minor (reflux, chest pain, and food impaction).

RESULTS

Mean survival was 4.5 months after stent placement (range, 3 weeks to 26 months). The overall incidence of delayed complications was 64.6%, with 17 patients (20.7%) experiencing more than one complication. The rates of delayed complications in patients with Z stents, Wallstents, and Ultraflex stents were 75.0%, 68.1%, and 44.4%, respectively (P <.05). Most complications were life-threatening and occurred more frequently when stents were placed in the proximal third of the esophagus, compared with more distally (P <.05). Thirteen patients (15.9%) died from complications directly related to stent placement.

CONCLUSION

Esophageal stent placement for malignant obstruction or fistula is associated with a substantial incidence of delayed complications.

Chest pain following oesophageal stenting for malignant dysphagia

AIM

The palliative use of self-expanding metallic stents has been widely reported to relieve dysphagia in cases of oesophageal carcinoma. Little has been documented on the severity of chest pain following oesophageal stenting. The aim of this study was to investigate the association of pain with oesophageal stenting for malignant dysphagia.

METHODS

Fifty-two patients with inoperable oesophageal carcinoma underwent stent placement between 1995-1999. Daily opioid analgesic requirements (mg of morphine equivalent doses) were monitored for 3 days before and 7 days after stenting. The degree of palliation was expressed as a dysphagia score (0-3). Hospital stay, readmission days, stent complications and patient survival time were also recorded.

RESULTS

Twenty-six patients (50%) required opioid analgesia for chest pain (median dose: 80 mg morphine/day) within 48 h of the procedure compared to 11 (21.2%) patients before stenting (P = 0.0041). A significant increase was evident in the analgesic consumption following stent deployment (P < 0.001). The dysphagia score improved by a median value of 1 (CI 0.25)P < 0.001, with a re-intervention rate of 11.5%. The median survival time was 40 days post stenting (range 1-120).

CONCLUSION

A significant proportion of patients developed chest pain after oesophageal stenting, requiring high dose opioid analgesia. As the origin of the pain is still unknown, pre-emptive analgesia may a play role in reducing stent-related morbidity and possibly in-hospital stay.