Malignant Esophageal Strictures Research Articles

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

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

Comprehensive review of materials, applications, and future innovations in biodegradable esophageal stents.

Esophageal stricture (ES) results from benign and malignant conditions, such as uncontrolled gastroesophageal reflux disease (GERD) and esophageal neoplasms. Upper gastrointestinal endoscopy is the preferred diagnostic approach for ES and its underlying causes. Stent insertion using an endoscope is a prevalent method for alleviating or treating ES. Nevertheless, the widely used self-expandable metal stents (SEMS) and self-expandable plastic stents (SEPS) can result in complications such as migration and restenosis. Furthermore, they necessitate secondary extraction in cases of benign esophageal stricture (BES), rendering them unsatisfactory for clinical requirements. Over the past 3decades, significant attention has been devoted to biodegradable materials, including synthetic polyester polymers and magnesium-based alloys, owing to their exceptional biocompatibility and biodegradability while addressing the challenges associated with recurring procedures after BES resolves. Novel esophageal stents have been developed and are undergoing experimental and clinical trials. Drug-eluting stents (DES) with drug-loading and drug-releasing capabilities are currently a research focal point, offering more efficient and precise ES treatments. Functional innovations have been investigated to optimize stent performance, including unidirectional drug-release and anti-migration features. Emerging manufacturing technologies such as three-dimensional (3D) printing and new biodegradable materials such as hydrogels have also contributed to the innovation of esophageal stents. The ultimate objective of the research and development of these materials is their clinical application in the treatment of ES and other benign conditions and the palliative treatment of malignant esophageal stricture (MES). This review aimed to offer a comprehensive overview of current biodegradable esophageal stent materials and their applications, highlight current research limitations and innovations, and offer insights into future development priorities and directions.

S2825 A Door to Relief: Severe Case of Malignant Esophageal Stricture Treated With a Biliary Stent

S2825 A Door to Relief: Severe Case of Malignant Esophageal Stricture Treated With a Biliary Stent

Impact of preoperative docetaxel, cisplatin, and 5-fluorouracil (DCF) therapy on degree of malignant esophageal stenosis

BackgroundMalignant esophageal stenosis is a common and severe complication of advanced esophageal cancer that can be a serious problem in the continuation of chemotherapy and other anticancer treatments. The impact of chemotherapy regimens on the degree of improvement in esophageal stenosis is unknown. In this study, we focused on the impacts of chemotherapy on the direct anticancer effects, and in the improvement of malignant stenosis.MethodsPatients who underwent radical esophagectomy after chemotherapy, either adjuvant 5-fluorouracil and cisplatin (FP) or docetaxel, cisplatin, and 5-fluorouracil (DCF) regimen, were included. We assessed the length of the cancerous stenosis, the width of the narrowest segment, and the size of the intraluminal area in the stenotic segment by fluoroscopy, and compared the differences before and after chemotherapy. In addition, we evaluated the dysphagia score (Mellow-Pinkas scoring system) as the evaluation of patients’ symptoms. The antitumor effects of chemotherapy were also investigated.ResultsA total of 81 patients were enrolled: 50 were treated with FP, and 31 were treated with DCF. The expansion rate in the length of the narrowest part was significantly increased in the DCF group compared with the FP group. Furthermore, the stenosis index (intraluminal stenotic area/stenotic length) was significantly increased in the DCF group compared with the FP group (112% vs 96%, P = 0.038). Dysphagia score after chemotherapy significantly improved in the DCF group compared to the FP group (P = 0.007). The response rates were 60% in the FP group and 67.7% in the DCF group. Effective histopathological response (improvement to grade 2 or 3) was 24% in the FP group and 38.8% in the DCF group.ConclusionDCF therapy is more effective than FP treatment in the improvement of malignant esophageal stenosis.

Self-expandable metallic stent-induced esophagorespiratory fistulas in patients with advanced esophageal cancer.

Self-expandable metallic stents (SEMSs) are widely adopted for the palliation of dysphagia in patients with malignant esophageal strictures. An important adverse event is the development of SEMS-induced esophagorespiratory fistulas (SEMS-ERFs). This study aimed to assess the risk factors related to the development of SEMS-ERF after SEMS placement in patients with esophageal cancer. This retrospective study was performed at the Instituto do Cancer do Estado de São Paulo. All patients with malignant esophageal strictures who underwent esophageal SEMS placement between 2009 and 2019 were included in the study. Of the 335 patients, 37 (11.0%) developed SEMS-ERF, with a median time of 129 days after SEMS placement. Stent flare of 28 mm (hazard ratio [HR], 2.05; 95% confidence interval [CI], 1.15-5.51; p=0.02) and post-stent chemotherapy (HR, 2.0; 95% CI, 1.01-4.00; p=0.05) were associated with an increased risk of developing SEMS-ERF, while lower-third tumors were a protective factor (HR, 0.5; 95% CI, 0.26-0.85; p=0.01). No difference was observed in overall survival. The incidence of SEMS-ERFs was 11%, with a median time of 129 days after SEMS placement. Post-stent chemotherapy and a 28 mm stent flare were associated with a higher risk of SEMS-ERF.

Role of Endoscopic Ultrasound-Guided Fine Needle Aspiration (EUS-FNA) in the Diagnosis of Suspicious Malignant Esophageal Strictures.

(1) Background: The accurate diagnosis of esophageal strictures is quite critical for optimizing medical intervention. However, the diagnosis of suspicious malignant esophageal strictures with intact mucosa appearance and negative biopsy results is challenging. This study aimed to evaluate the role of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in the diagnosis of suspicious esophageal strictures. (2) Methods: We retrospectively analyzed the cases with suspicious malignant esophageal strictures that underwent EUS-FNA, with or without rapid on-site evaluation (ROSE), in our hospital from April 2017 to September 2022. Their clinical manifestations, imaging examinations, gastroscopic examinations, EUS-FNA results, and therapeutic strategies were retrospectively recorded and analyzed. (3) Results: A total of 23 patients (15 male and 8 female) were enrolled in this study. Based on EUS-FNA results, 18 patients were diagnosed with malignancies, including 16 cases of primary esophageal cancer (13 squamous carcinomas and 3 adenocarcinomas), 1 case of mediastinal cancer, and 1 case of metastatic esophageal cancer; 1 case of tuberculosis was also confirmed by EUS-FNA. Among 4 cases of ambiguous diagnosis with EUS-FNA, 1 was diagnosed with an esophageal glomus tumor after surgical removal, and 2 patients survived for several years without medical intervention, which hinted at the possibility of benign esophageal strictures. No major complications, including bleeding or perforation, were observed. (4) Conclusions: EUS-FNA may serve as a safe and effective diagnostic tool in suspicious malignant esophageal strictures with accurate specimen acquisition, especially for biopsy-negative cases.

Comparison of outcome of rigid and self-expanding stents for palliation of malignant dysphagia

Between 1984 and 2019, 1005 rigid prostheses and 423 self-expanding stents were inserted for palliation of malignant esophageal stenosis. The aim of this study was the comparison of the treatment results using the two types of prosthesis. Retrospective analysis has been performed comparing the characteristics and treatment results of the two patients groups referring to the technical success of the procedures, procedure-related complications, change in the quality of life, and survival time. A comparison of average ages, duration time of dysphagia, quantity of weight loss, and the progress of the malignancy proves that palliation with self-expanding stents made it possible to treat more patients in worse condition. The number of complications in the patient group treated with stents was significantly higher at 29.3%/20.9%. Endoscopic intervention was performed to treat complications in 68.6% of cases with rigid prostheses and in 53.2% of patients treated with stents. Relevant improvement of dysphagia and the patients' quality of life was observed in 97% of those who were treated with a rigid prosthesis and in 91.3% of those who were treated with self-expanding stents. The survival time in the group of patients treated with stents was significantly shorter by 4.3/5.4 months than in the other group. The use of self-expanding stents in palliative treatment of malignant strictures have brought significant changes in everyday practice with increasing the possibilities. The treatment results were not improved by their application as much as the worse condition of the patient group worsened them. Orv Hetil. 2022; 163(49): 1952-1961.

Niti-S Esophageal Covered stent (double anti-reflux type). An observational patient registry/post-market clinical follow-up study.

Relieving dysphagia is the main goal of palliative care in advanced esophageal cancer. We aimed to evaluate the safety and clinical performance of the Niti-S esophageal double covered, anti-reflux stent (Taewoong Medical, Seoul, Korea) in inoperable carcinoma of the esophagus or gastric cardia. This was a retrospective patient registry/post-market clinical follow-up study of all patients with esophageal malignant strictures undergoing self-expandable metal stent (SEMS) placement with the Niti-S Esophageal covered stent, double antireflux in a community hospital (AZ St Maarten Mechelen, Belgium) between March 2013 and July 2021. In twenty-nine patients, thirty self-expandable metal stents (SEMS) were placed. The median dysphagia score before stent placement was 3 and 0 after stent placement (p < 0.001). Stent migration did not occur. Two patients (7%) had new onset reflux symptoms. The most common adverse event was retrosternal pain (5 patients, 17%). One patient (3%) had recurrent dysphagia due to proximal tumoral overgrowth and two patients (7%) because of proximal benign tissue overgrowth. There were no perforations, fistula formations or episodes of food impaction. The Niti-S esophageal double covered, antireflux stent (Taewoong Medical, Seoul, Korea) is an effective and safe treatment option for malignant esophageal stenosis.

Inversion technique under fluoroscopy for removal of self-expanding nitinol esophageal stent after long-term placement: review of 107 consecutive cases.

Removal of self-expanding esophageal metal stents that have been implanted for a long time can be difficult and risky. In this paper, we describe the use of the "inversion technique" under fluoroscopy for removal of self-expandable nitinol esophageal stents that have been placed for long periods and evaluate the effectiveness and safety of the method. Retrospective analysis of patients who underwent removal of self-expanding nitinol esophageal stents by the inversion technique under fluoroscopy at our center. Demographic characteristics, type of esophageal stents, stent retention time, reasons for stent removal, and related complications were collected from the case records and analyzed. A total of 112 metal esophageal stents (62 fully covered esophageal stents and 50 partially covered esophageal stents) were extracted from the 107 patients included in the study. Indications for stent implantation were malignant esophageal stenosis (27 patients), benign esophageal stenosis (42 patients), and esophageal fistula (38 patients). Median duration of stent retention was 77days (29-727days). All stents were removed successfully without major complications such as esophageal rupture, massive hemorrhage, asphyxia, or cardiorespiratory arrest. Inversion technique under fluoroscopy appears to be a safe, effective, and quick procedure for removal of self-expanding nitinol esophageal stent after long-term placement.

Endoscopic ultrasound-guided fine needle aspiration for smooth benign appearing malignant esophageal stricture: a cross-sectional study.

BackgroundEndoscopic biopsy is standard for the diagnosis of esophageal malignancy. However, few cases are difficult to diagnose as they present with smooth esophageal stricture with negative biopsy results. We aimed to evaluate the effectiveness and safety of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in the diagnosis of biopsy-negative suspected malignant esophageal strictures.MethodsWe retrospectively analyzed cases of esophageal stricture with negative biopsies. From September 2016 to November 2021, 50 patients were enrolled. All the patients accepted the EUS-FNA examination. And histological and cytological specimens were obtained from all patients. Clinical, endoscopic, imaging, cytological, and histopathological results were noted and analyzed.ResultsA total of 50 patients (40 male and 10 female) were enrolled in this study. The 19G puncture needle was used in 6 cases and the 22G puncture needle was used in 44 cases; an average of 2.7 needles were used per case. Satisfactory specimens were obtained by EUS-FNA for all subjects. All patients were diagnosed as malignant tumor. The diagnosis was confirmed by EUS-FNA biopsies in 98% of patients. Based on the surgical pathology results, there were 16 cases of esophageal squamous cell carcinoma, 2 cases of esophageal metastatic carcinoma, 1 case of esophageal sarcoma, 22 cases of lung cancer, 6 cases of mediastinal lymph node metastasis, and 3 cases of mediastinal tumor. No obvious complications were observed. A total of 5 cases were treated with surgery, 28 with chemotherapy, 3 with chemotherapy + surgery, and 12 with radiotherapy; 2 patients ceased treatment. No obvious complications, such as bleeding and mediastinal infection, were observed.ConclusionsEUS-FNA is effective and safe for the diagnosis of malignant esophageal strictures with smooth overlying esophageal mucosa. EUS-FNA is effective and safe for patients with smooth esophagus stenosis for whom satisfactory cytological and histological specimens can be obtained, and the diagnosis can be confirmed by cytological, histological, and immunohistochemical examinations. It can be used as the first choice for diagnosis and treatment.

Contactless Measurement of Integrity of Silicone Coating on Self-Expandable Esophageal Nitinol Stents.

A stent is a mesh tube inserted into a natural passage in the body to prevent disease induction. Self-expandable esophageal nitinol stents such as SX-ELLA Stent Esophageal HV (HV Stent Plus) can be indicated for palliation of malignant esophageal strictures, for the treatment of benign esophageal strictures that are refractory to standard therapy and for the treatment of esophago-respiratory fistulas. A silicone-stent coating is used for tumor in-growth prevention and esophago-respiratory fistula occlusion. The thickness of the stent and the overall integrity of the silicone coating of all wires indicate the overall mechanical properties of the esophageal stent and the resistance to external adverse events such as corrosion and mechanical and chemical resistance. The polymer multicomponent epoxy resin - a mixture of Epon and Durcupan - was used as a method for robust sample stabilization. A cutting system using a thin water beam with a powder (Blue Line) was chosen as the best variant to obtain 6 samples for both-sided measurement (10 measuring sides). The optical microscopic reflective light method was used to examine wire crossing points in the sections. Fifty values were measured on either sample side for the internal, external and mesh thickness of the silicone stent layer. The wire crossing points were selected so that the silicone layer structure could be clearly seen, and the wires approached each other most closely. Only approximately 4 to 8 crossing points in each section could be measured when applying this approach. The resolution of the microscope and calibration (based on the camera used) was 0.677 μm/pixel. Additional data could be obtained on 8 planes. Two boundary samples were destroyed by the cutting process. Whole coating of the stent was around all mesh wires, especially in areas with higher mechanical stress (wire crossing). The minimum detectable and admissible value determined for all 3 measuring areas (internal, external, mesh) on the wire crossings was 6.77 μm, i.e., 10 pixels, based on the microscope resolution and manufacturer's methodology. The results were characterized by p < 0.001 for all 3 parameters. We tested opposite samples in each section to verify the section quality and data consistency. For the 4 areas, the data were significantly different, but the thickness differences were only on the order of units percent, so the measurements were not appreciably affected. We assume that the material cutting loss, making up 1-2 mm, contributed to the differences in the sections. We examined the overall integrity of the silicone coating of the esophageal stent. The method of HV stent anchoring in a polymeric bath followed by cutting with a waterjet and sample measurement under an optical microscope proved to be very simple and reliable. Sufficient thicknesses of the silicone layer on the wire cross sections were verified. The coated silicone layer thickness appeared to be significantly different along the stent from the proximal part to the distant part, presumably due to the manufacturing technology.

Complications of endoscopic esophageal stent implantation

Endoscopic esophageal stent implantation is an effective method for dysphagia management in malignant esophageal stricture. However, this technology is associated with the risk of many complications, including those fatal to life. These include bleeding, restenosis, stent fragmentation and destruction, stent migration, pneumomediastinum, the formation of esophageal fistulas, perforations, clogging of the stent with food, retrosternal pain, gastroesophageal reflux changes, airway compression, aspiration pneumonia, and fever. The overall complication rate is 3640%. Mortality rates associated with stenting is between 3.9 and 27.2%. Nevertheless, today there are ways to minimize the incidence of complications due to the constant progress of endoscopic technologies and improvements in the design of modern stents. In addition, most endoscopic interventions can manage the vast majority of complications effectively after stent implantation subject to their early detection. Optimal selection of an esophageal stent and careful selection of patients with a low risk of complications associated with stent implantation are important problems in the prevention of complications to achieve high efficiency of stenting. Evaluation of risk factors for possible complications, the design of stents and their characteristics, as well as using modern methods of effective management of possible complications improves the quality and duration of life in incurable patients with esophageal cancer. The review reflects all possible complications of stenting in esophageal and gastroesophageal junction, factors affecting the occurrence of complications, as well as modern and effective methods of their correction and prevention.

A Phase II Study of Biodegradable Stents Plus Palliative Radiotherapy in Oesophageal Cancer

AimsSelf-expanding metal stents provide rapid improvement of dysphagia in oesophageal cancer but are associated with complications. The aim of the present study was to test the effectiveness of an alternative treatment of combining biodegradable stents with radiotherapy. Materials and methodsA Simon two-stage single-arm prospective phase II trial design was used to determine the efficacy of biodegradable stents plus radiotherapy in patients with dysphagia caused by oesophagus cancer who were unsuitable for radical treatment. Fourteen patients were recruited and data from 12 were included in the final analyses. ResultsFive of 12 patients met the primary end point: one stent-related patient death; four further interventions for dysphagia within 16 weeks of stenting (41.7%, 95% confidence interval 15.2–72.3%). The median time to a 10-point deterioration of quality of life was 2.7 weeks. Nine patients died within 52 weeks of registration. The median time to death from any cause was 15.0 weeks (95% confidence interval 9.6–not reached). ConclusionThe high re-intervention observed, which met the pre-defined early stopping criteria, meant that the suggested alternative treatment was not sufficiently effective to be considered for a larger scale trial design. Further work is needed to define the place of biodegradable stents in the management of malignant oesophageal strictures.

Palliation in Malignant Esophageal Stricture and Fistulas with Self-expandable Metallic Stents

Palliation in Malignant Esophageal Stricture and Fistulas with Self-expandable Metallic Stents

Stenting of the esophagus in the course of the malignant dysphagia in elderly patients

Esophageal cancer is a disease with difficult clinical management, and palliative therapy is the only predominant treatment. This retrospective study analyses the results of clinical management of elderly patients (&gt;75 years of age) who were treated with esophageal stenting for malignant dysphagia due to primary esophageal cancer, including squamous cell carcinoma (SCC), esophageal adenocarcinoma (EAC), as well as secondary esophageal malignant strictures due to non-small cell lung cancer (NSCLC). Patients with esophago-respiratory fistula (ERF) were also included in the study. This study included 166 patients aged 75–88 (mean age, 78) years. Nine (5.4%) patients had upper malignant esophageal stenosis, 48 (28.1%) had the middle, 43 (25.9%) in the lower part of the esophagus, 49 (29.5%) patients had EAC-related stenosis, and 17 (10.2%) patients reported lung cancer-related esophageal stenosis. Dysphagia was rated at 2.8 (range, 2–3) before stenting and at 1.2 (range, 1–2) after the stenting procedure. Seven (4%) patients experienced stenting migration, 12 (7.2%) had granulation tissue overgrowth and prosthesis obstruction, two (1.2%) developed respiratory failure, and one (0.6%) patient died. Twelve (7.2%) patients were treated for ERF with double-stenting, and three (1.8%) patients developed a secondary fistula after the stent implantation. The mean survival of patients with esophageal cancer and ERF was 101.8 days and 62.5 days, respectively. Esophageal stenting has proven a safe procedure in patients over 75 years of age. It has a low rate of stenting obstruction and migration. Patients with ERF are a particularly difficult group to treat, show very poor outcomes and short survival rates.

Performance and Predictors of Migration of Partially and Fully Covered Esophageal Self-Expanding Metal Stents for Malignant Dysphagia

Self-expanding metal stents (SEMS) are routinely used to palliate malignant dysphagia. However esophageal SEMS can migrate or obstruct due to epithelial hyperplasia. The aim of this study was to evaluate the rates and factors predicting migration and obstruction, and the nutritional outcomes in partially covered (pc) vs. fully covered (fc) SEMS vs. fcSEMS with antimigration fins (AF) placed for malignant dysphagia. A retrospective review of consecutive patients undergoing SEMS placement for malignant dysphagia at three academic medical centers. Among 357 patients, there were 55 (15.4%) stent migrations, 45 (12.6%) obstructions from epithelial hyperplasia, and 20 (5.6%) food impactions. Median overall survival was 79 days (IQR 41,199). The percent weight change/change in albumin at 30 and 60 days after SEMS placement were -2.24%/-0.544 g/dL and -2.98%/-0.55 g/dL, respectively. Stent migration occurred significantly more often with fcSEMS than pcSEMS (25.3% vs 10.9%; P < .003), but there was no difference when either group was compared to fcSEMS-AF (19.3%). The overall rate of epithelial hyperplasia resulting in stent obstruction was low (12.6%) and not different between stent types. Factors associated with increased risk of SEMS migration on multivariable logistic regression included stricture traversability with a diagnostic endoscope (OR,2.37; 95% CI, 1.29-4.35) and use of fcSEMS (OR, 2.56; 1.31-5.00) or fcSEMS-AF (OR, 2.30, 1.03-5.14). Traversability of a malignant esophageal stenosis predicts SEMS migration. In these patients with a limited overall survival, pcSEMS are associated with lower rates of stent migration and similar rates of obstruction compared to fcSEMS.

Balloon Dilation for Endosonographic Staging in Esophageal Cancer: A Phase 1 Clinical Trial

Dilation in patients with malignant esophageal strictures precluding the passage of the endoscopic ultrasonography (EUS) scope allows complete evaluation; however, it may be associated with complications. This study evaluates the safety and clinical value of balloon dilation to complete EUS in patients with stenotic esophageal cancers. This study consists of a phase I clinical trial. One-hundred-and fifty patients were recruited. Endoscopic balloon dilation was performed before EUS in patients with high-grade stenosis. The analysis was focused on the ability to complete an endosonographic examination after dilation, 30-day morbidity, and change in the final stage or definitive management based on the completed endosonographic examination. Dilation was required in 55 patients (36.7%), with a complication rate of 10.9% (n= 6). Dilation allowed completion of EUS in 53 patients (96.4%), leading to a modification of the clinical stage for 18 patients (34%) and a deviation in the treatment plan in 7 patients (13.2%). No differences were found in these variables when compared with the group that did not require dilation (26.3% and 14.7%, P= .33 and P= .79, respectively). Dilation was associated with more advanced disease on final pathology among patients who underwent surgical resection (P= .006). High-grade malignant esophageal strictures that preclude the passage of the ultrasound probe are associated with advanced stage disease. Owing to the high risk of perforation and the limited benefit in staging, balloon dilation to complete the EUS staging should be avoided. (Clinicaltrials.gov identifier: NCT01950442.).

RoSE: A Robotic Soft Esophagus for Endoprosthetic Stent Testing.

Soft robotic systems are well suited for developing devices for biomedical applications. A bio-mimicking robotic soft esophagus (RoSE) is developed as an in vitro testing device of endoprosthetic stents for dysphagia management. Endoprosthetic stent placement is an immediate and cost-effective therapy for dysphagia caused by malignant esophageal strictures from esophageal cancer. However, later stage complications, such as stent migration, could weaken the swallow efficacy in the esophagus. The stent radial force (RF) on the esophageal wall is pivotal in avoiding stent migration. Due to limited randomized controlled trials in patients, the stent design and stenting guidelines are still unconstructive. To address the knowledge deficit, we have investigated the capabilities of the RoSE by implanting two stents (stent A and B) of different radial stiffness characteristics, to measure the stent RF and its effect on the stent migration. Also, endoscopic manometry on the RoSE under peristalsis has been performed to study the impact of stenting and stent dysfunctionality on the intrabolus pressure signatures (IBPSs) in the RoSE, and further its effects on the swallowing efficacy. Each implanted stent in the RoSE underwent a set of experiments with various test variables (peristalsis velocity and wavelength, and bolus concentrations). In this study, the conducted tests are representative of the application of RoSE to perform a wide-ranging assessment of the stent behavior. The usability of RoSE has been discussed by comparing the results of stent A and B, for various combinations of the test variables mentioned earlier. The results have demonstrated that the stiffer stent B has a higher RF, whereas stent A maintained its RF at a low profile due to its lesser stiffness. The results have also implicated that a high RF is necessary to minimize the stent migration under prolonged peristaltic contractions in the RoSE. For the manometry experiments, stent A slightly increased the IBPS, but the stiffer stent B significantly decreased the IBPS, especially for the higher concentration boluses. It was found that if a stiffer stent buckles, it can reduce the swallow efficacy and cause recurrent dysphagia. Therefore, RoSE is an innovative soft robotic platform that is capable of testing various endoprosthetic stents, thereby offering a solution to many existing clinical challenges in the area of stent testing.

Bilateral vocal cord paralysis after endoscopic placement of fully covered self-expandable metal stent for palliative treatment of malignant proximal esophageal obstruction: two case reports

BackgroundOesophageal stents have several well-known respiratory complications, including aspiration pneumonia, fistula and airway compression. However, bilateral vocal cord paralysis has rarely been described.MethodsWe describe two patients who presented with refractory dysphagia due to malignant proximal oesophageal strictures. Both received palliative treatment consisting of fully covered self-expandable metal stents that were placed across the strictures.ResultsBoth patients developed inspiratory stridor and acute hypoxemic respiratory failure shortly after the stent was placed. Flexible bronchoscopy revealed vocal cord paralysis in paramedian position, potentially due to extrinsic compression of the posterior branch of the recurrent laryngeal nerve following the progressive opening of the esophageal prosthesis. One patient recovered after the stent was removed.ConclusionsBilateral vocal cord paralysis is a rare but potentially fatal complication of proximal esophagus stenting.

Radioactive feeding tube in the palliation of esophageal malignant obstruction.

A radioactive feeding tube was used to achieve both nutrition and brachytherapy for the treatment for malignant esophageal obstruction. We report the safety and effectiveness of this technique. We conducted a retrospective analysis of 16 consecutive patients who employed this technique from January 2015 to March 2018. The radioactive feeding tube was made by binding the 125I seed chain on the feeding tube. Under fluoroscopic guidance, the tube was inserted into the obstructed esophagus, with the seed chain crossing over the segment of malignant esophageal obstruction. Technical success rate, dysphagia score, procedure time and complications were analyzed. Kaplan-Meier analysis was used to analyze the survival time. The radioactive feeding tube was easy to prepare. The technical success rate was 100%, without serious complications such as bleeding or infection. The median procedure time of tube insertion was 44.0min. The Kamofsky score and Neuhaus dysphagia grading were significantly improved after tube insertion (p < 0.01). On esophageal radiography, the contrast agent passed through the narrow area smoothly. Complete remission (n = 1) and partial remission (n = 13) of local tumor were obtained in 14 patients, and the local tumor control rate was 87.5% (14/16). During follow-up, four patients survived with no obvious clinical symptom and 10 patients died of cancer. The median survival was 12.0months. Preparation of the radioactive feeding tube is simple and easy. The insertion of this kind of tube achieves parenteral nutrition and brachytherapy simultaneously and is safe and effective in dysphagia palliation of malignant esophageal stricture. The radiological-radiotherapeutic procedure could be an alternative tool in the case of refusing other treatments by the patients.