Esophageal stenting in the setting of malignancy

Tracheoesophageal fistula development following radiotherapy and tyrosine kinase inhibitors in a patient with advanced follicular thyroid carcinoma: a case-based review

INTRODUCTION

Tracheoesophageal fistulas (TEF) are a rare complication that can occur in patients with radioactive iodine refractory metastatic follicular thyroid carcinoma (FTC) following treatment with radiotherapy (RT) and tyrosine kinase inhibitors (TKI).

METHODS

We describe the case of a TEF development in a 69-year-old male who underwent targeted therapy TKIs and adjuvant RT for radioactive iodine refractory FTC.

RESULTS

In the case, staging investigations revealed a metastatic, poorly differentiated FTC refractory to radioactive iodine. After 2 years of disease control on Lenvatinib, the patient's condition progressed, necessitating a switch to Cabozantinib. Soon after, they presented with haemoptysis secondary to invasion of the primary thyroid tumour into the trachea. Radical radiotherapy (45 Gy/30 fractions) was also administered to the thyroid gland, ultimately complicated by radiation necrosis. Four months post-completion of RT and recommencing TKI, the patient presented with haemoptysis and hoarseness secondary to recurrent laryngeal nerve compression and tracheal invasion, as well as dysphagia secondary to oesophageal compression. Following an acute presentation with intractable throat pain, investigations revealed a TEF. Surgical and endoscopic management was deemed inappropriate given the patient's rapid deterioration and anatomical position of the TEF, and therefore a palliative approach was taken.

CONCLUSION

This case report highlights a rare cause of TEF development in a patient having TKI therapy post-RT for advanced FTC. It highlights the importance of monitoring TEF development in this cohort of patients. It demonstrates the importance of patient counselling and education regarding treatment options and the rare side effects of treatments.

X-ray-guided self-expandable metal stent (SEMS) implantation in oesophageal malignancy as an alternative treatment

<b><br>Indroduction:</b> Significant dysphagia, aspiration pneumonia, and impossible oral nutrition in patients with unresectable or recurrent gastroesophageal malignancy or bronchial cancer invading the oesophagus with a tracheoesophageal fistula lead to cachexia. Dehiscence of the esophago-jejunal or gastroesophageal anastomosis may cause severe oesophageal haemorrhage. We believe that X-ray-guided oesophageal stent implantation (SEMS) is an alternative palliative method for microjejunostomy or full parenteral nutrition.</br> <b><br>Aim:</b> The aim of this paper was to assess the safety and efficacy of a novel X-ray-guided oesophageal stent implantation technique.</br> <b><br>Materials and methods:</b> This retrospective analysis included 54 patients (35 men and 19 women) treated for malignant dysphagia, gastroesophageal/gastrointestinal anastomotic fistula or bronchoesophageal fistula in two Surgical Units between 2010 and 2019, using a modified intravascular approach to oesophageal stent implantation.</br> <b><br>Results:</b> The presented modified intravascular method of oesophageal stent implantation was successfully performed in all described patients requiring oral nutrition restoration immediately following oesophageal stent implantation. Two patients with oesophageal anastomotic dehiscence died on postoperative days 7 and 9 due to circulatory and respiratory failure. One patient was reimplanted due to a recurrent fistula. Two patients with ruptured thoracic aneurysm and thoracic stent graft implantation due to oesophageal haemorrhage, who were implanted with an oesophageal stent, died on postoperative days 4 and 14.</br> <b><br>Conclusions:</b> The modified intravascular X-ray-guided SEMS technique may be a palliative treatment for patients with unresectable oesophageal malignancies.</br>.

A Successful Treatment of Broncho-Esophageal Fistula with Esophageal Stenting Using Direct Endoscopic Visualization

Broncho-esophageal fistula (BEF) is a severe yet relatively rare connection between the bronchus and esophagus usually caused by esophageal and pulmonary malignancies. We present a case report of a 49-year-old man diagnosed with terminal lung carcinoma who developed a BEF. The thoracic computed tomography scan detected a mass in the left bronchi that partially covers and disrupts the bronchial contour in certain regions and extends to the esophageal wall. After thoroughly evaluating alternative treatment approaches, we opt for the stenting procedure due to the advanced stage of the tumor and the significantly diminished quality of life. The treatment involves the use of a partially covered metal stent that is known to exhibit lower potential to migrate. The treatment is highly successful, resulting in a significant enhancement of the patient's quality of life, a lengthening in his survival, and the ability to pursue additional palliative treatment options. In contrast to the typical prosthesis implantation, our procedure uses a direct endoscopic visualization for the proximal deployment of a partially covered stent, offering a cost-effective and radiation-free alternative that can be particularly beneficial for BEF patients in facilities without radiology services.

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.

The endoscopic management of oesophageal strictures

An oesophageal stricture refers to a narrowing of the oesophageal lumen, which may be benign or malignant. The cardinal feature is dysphagia, and this may result from intrinsic oesophageal disease or extrinsic compression. Oesophageal strictures can be further classified as simple or complex depending on stricture length, location, diameter, and underlying aetiology. Many endoscopic options are now available for treating oesophageal strictures including dilatation, injectional therapy, stenting, stricturotomy, and ablation. Self-expanding metal stents have revolutionised the palliation of malignant dysphagia, but oesophageal dilatation with balloon or bougienage remains first-line therapy for most benign strictures. The increase in endoscopic and surgical interventions on the oesophagus has seen more benign refractory oesophageal strictures that are difficult to treat, and often require advanced endoscopic techniques. In this review, we provide a practical overview on the evidence-based management of both benign and malignant oesophageal strictures, including a practical algorithm for managing benign refractory strictures.

Management of Esophageal Squamous Cell Carcinoma With Esophageal Stent Placement in an Elderly Patient With Dysphagia

Esophageal cancer is typically identified as squamous cell carcinoma or adenocarcinoma. There are multiple risk factors that may contribute to esophageal squamous cell carcinoma including smoking, alcohol consumption, and the human papillomavirus. Lesions may appear ulcerated, friable, and circumferential and may obstruct the esophagus. Therefore, patients may complain of non-specific symptoms including dysphagia, weight loss, and retrosternal discomfort. Clinicians often rely on an upper endoscopy with biopsy to confirm the diagnosis. Computed tomography scans and endoscopic ultrasounds are also employed to assess the extent of malignant spread. Management may involve endoscopic resection for superficial lesions or surgical resection for lesions penetrating the submucosa. Esophageal stents may play a role, specifically as a palliative measure for enhancing oral intake. We present an instance of utilizing a self-expandable, metal-covered esophageal stent with balloon dilation in the setting of a newly diagnosed esophageal squamous cell carcinoma lesion in a 73-year-old female. Ultimately, the use of an esophageal stent in this patient helped improve the patient's oral intake during her course of hospitalization. Her diet was slowly advanced to clear liquids and progressively to a low-residue diet before being discharged to follow-up with her diagnosis as outpatient with gastroenterology.

[Palliative endoscopy]

Endoscopy is the leading method in the diagnostics of gastrointestinal malignancies. With the increasing incidences of various tumor entities, a palliative treatment situation is already present in many patients despite an increasing number of screening strategies. Palliative endoscopy can make an essential contribution to alleviation of tumor-related symptoms, such as dysphagia, malnutrition, cholestasis, ileus and pain. Various approaches can be offered to safeguard the nutrition, e.g. percutaneous endoscopic gastrostomy (PEG) and percutaneous endoscopic jejunostomy (PEJ), for maintenance of the gastrointestinal passage (stents) and secretion drainage or to drain congested hollow organs. Furthermore, in cases of inaccessibility or impassability of stenoses due to tumors, endosonographically assisted punctures offer the possibility to guarantee new drainage options or continuities by stent placement. In all interventions possible contraindications and complications must be taken into account.

Salvage therapy of bleeding esophageal tumor by fully covered self-expandable metallic stent: A case report

The role of self-expandable metallic stents is gradually evolving for a diverse group of benign and malignant gastrointestinal tract problems, with luminal obstruction being by far the most common. Although its role in refractory variceal bleeding is well established, it has rarely been tried for tumor-related bleeding, with only a few case reports in this regard. We share our experience of successfully controlling esophageal tumor–related bleeding with the use of a fully covered self-expandable metallic stent. A 58-year-old woman with irresectable distal esophageal cancer, presented with hematemesis. Esophago-gastro-duodenoscopy revealed an obstructing esophageal tumor with diffuse oozing of blood. This was unamenable to local injection of adrenaline and hemospray; therefore, a temporary self-expandable metallic stent was parked to create a tamponade effect. This successfully stopped bleeding and the patient remained asymptomatic till discharge. However, she was lost to follow-up, and therefore, the stent was removed after a period of 5 months instead of 2 weeks.

Palliative Radiotherapy Versus Esophageal Stent Placement in the Management of Patients With Metastatic Esophageal Cancer

Background:Patients with advanced esophageal cancer often experience pain and dysphagia, yet the optimal palliative management remains unclear. This retrospective study evaluated outcomes and adverse effects of palliative radiotherapy (RT) compared with esophageal stenting among a cohort of U.S. veterans with metastatic esophageal cancer.Patients and Methods:We identified 1,957 veterans in the United States with metastatic esophageal cancer who received palliative RT to the esophagus or esophageal stenting, and assessed the risks of severe adverse effects, including esophageal fistula formation, perforation, obstruction, hemorrhage, and esophagitis. We determined palliative efficacy by evaluating pain and dysphagia scores before and after intervention. Multivariable analyses were used to control for potential confounding factors.Results:In our cohort, 1,593 patients underwent RT and 364 underwent esophageal stenting. The cumulative incidence of any severe adverse effect at 6 months was higher among patients who received stents compared with those who received RT (21.7% vs 12.4%;P<.0010). In multivariable analysis, patients who received stents had an increased risk of any severe adverse effect, including fistula, perforation, and hemorrhage (allP<.0500). Multivariable analysis also showed that, compared with stenting, RT was associated with more rapid and durable pain relief (P<.0010) with no difference in relief of dysphagia over time when accounting for pretreatment dysphagia scores (P=.1029).Conclusions:Compared with esophageal stenting, RT was associated with a decreased risk of adverse effects, greater pain relief, and equivalent relief of moderate to severe dysphagia over time. Unmeasured patient- or tumor-related factors could have influenced the choice of intervention, thereby impacting our study outcomes. To our knowledge, this is the largest study to date analyzing the comparative risks and benefits of palliative RT and esophageal stenting among patients with metastatic esophageal cancer.

Nanoparticle-Embedded Electrospun Fiber-Covered Stent to Assist Intraluminal Photodynamic Treatment of Oesophageal Cancer

Drug-eluting stents (DESs) are promising candidates for treating human oesophageal cancer. However, the use of DESs to assist photodynamic therapy (PDT) of orthotopic oesophageal tumors is not yet demonstrated to the best of current knowledge. Herein, through an electrospinning technology it is shown that oxygen-producing manganese dioxide nanoparticles are embedded into elelctrospun fibers, which are subsequently covered onto stents. Upon implantation, the nanoparticles are gradually released from the fibers and then diffuse into the nearby tumor tissue. Then, the hypoxic microenvironment can be effectively alleviated by reaction of MnO₂ with the endogenous H₂ O₂ within the tumor. After demonstrating the excellent PDT efficacy of the stents in a conventional subcutaneous mouse tumor model, such stents are further used for PDT treatment in a rabbit orthotopic oesophageal cancer model by inserting an optical fiber into the tumor site. Greatly prolonged survival of rabbits is observed after such intraluminal PDT treatment. Taken together, this work shows that the fiber-covered stent as a nanoparticle delivery platform can enable effective PDT as a noninvasive treatment method for patients with advanced-stage oesophageal cancer.

Biomaterials in Gastroenterology: A Critical Overview

In spite of the large diversity of diagnostic and interventional devices associated with gastrointestinal endoscopic procedures, there is little information on the impact of the biomaterials (metals, polymers) contained in these devices upon body tissues and, indirectly, upon the treatment outcomes. Other biomaterials for gastroenterology, such as adhesives and certain hemostatic agents, have been investigated to a greater extent, but the information is fragmentary. Much of this situation is due to the paucity of details disclosed by the manufacturers of the devices. Moreover, for most of the applications in the gastrointestinal (GI) tract, there are no studies available on the biocompatibility of the device materials when in intimate contact with mucosae and other components of the GI tract. We have summarized the current situation with a focus on aspects of biomaterials and biocompatibility related to the device materials and other agents, with an emphasis on the GI endoscopic procedures. Procedures and devices used for the control of bleeding, for polypectomy, in bariatrics, and for stenting are discussed, particularly dwelling upon the biomaterial-related features of each application. There are indications that research is progressing steadily in this field, and the establishment of the subdiscipline of "gastroenterologic biomaterials" is not merely a remote projection. Upon the completion of this article, the gastroenterologist should be able to understand the nature of biomaterials and to achieve a suitable and beneficial perception of their significance in gastroenterology. Likewise, the biomaterialist should become aware of the specific tasks that the biomaterials must fulfil when placed within the GI tract, and regard such applications as both a challenge and an incentive for progressing the research in this field.

Fully-covered esophageal stent migration rates in benign and malignant disease: a multicenter retrospective study

Background and study aims  Stent migration is a common complication of fully-covered self-expanding metal stents (FCSEMS), but the rate of clinically relevant migration as defined by stent migration followed by reintervention via endoscopy for stent replacement is unknown. The goal of this study is to gain insight into the total migration rate and clinically relevant migration rate of different types of FCSEMS placed within benign and malignant strictures with specific attention paid to stent manufacturer, diameter, and length. Patients and methods  Multicenter retrospective analysis of endoscopic data from patients with FCSEMS placed within benign or malignant strictures. FCSEMS used included a variety of sizes and manufacturers. Results  A total of 369 patients were included, 161 of whom had benign strictures and 208 of whom had malignant strictures. The total migration rate and clinically relevant migration rate in benign strictures were 30 % and 17 %, respectively. For benign strictures, Wallflex stents had a clinically relevant migration rate of 15 %, compared to Endomaxx stents with 19 %, and Evolution stents with 25 % ( P  = 0.52). The total migration rate and clinically relevant migration rates in malignant strictures were 23 % and 14 %, respectively. Evolution stents had a significantly higher clinically relevant migration rate (29 %) than the Wallflex stents (7 %) and the endomaxx stents (12 %), P  = 0.003. Conclusion  This study is the largest to investigate migration rates for FCSEMS in benign and malignant strictures. Clinically relevant migration is a relatively common occurrence with all stent types studied and better anti-migration features are needed.

A Review of Self-Expanding Esophageal Stents for the Palliation Therapy of Inoperable Esophageal Malignancies

Esophageal cancer is a very deadly disease, killing more than 15,000 people in the United States annually. Almost 400,000 new cases happen in the worldwide every year. More than 50% esophageal cancer patients are diagnosed at an advanced stage when they need an esophageal stent to open the blocked esophagus for feeding and drinking. Esophageal stents have evolved in stages over the years. Current clinically used stents commonly include stainless steel or nitinol self-expandable metallic stent (SEMS) and self-expandable plastic stent (SEPS). There are many choices of different types of stents and sizes, with fierce competition among manufacturers. However, current stent technology, whether uncovered, partially covered, fully covered SEMS or SEPS, has their own advantages to solve the dysphagia, stricture, and fistula problems, but they also cause some clinical complications. The ideal stent remains elusive. New 3D printing technique may bring new promising potential to manufacturing personalized esophageal stents. Drug-eluting stents could be the new avenue to do more than just pry open a stricture or cover a defect in the esophageal lumen, a possibility of proving local anticancer therapy simultaneously. Additionally, the lack of esophageal cancer animal models also hinders the progress of stent development. This paper reviews these topics for a comprehensive understanding of this field. In a conclusion, the ultimate goal of the future esophageal stent would have multifunction to treat the underlying conditions and restore esophageal function to near normal.

Complications after treating esophageal strictures with prostheses and stents - 20 years' experience

INTRODUCTION

Over 80% of patients with esophageal cancer are qualified only for palliative treatment. The main goal of the therapy is to eliminate symptoms of dysphagia.

AIM

To analyze complications after insertion of prostheses and stents in patients with inoperable cancer of the esophagus/cardia.

MATERIAL AND METHODS

From 1996 to 2015 prostheses of the esophagus were implanted in 1309 patients. In the strictures of the lower part of the esophagus, Barbin-Mousseau prostheses (102 cases) and Häring prostheses (324 cases) were placed. In the strictures of the upper and middle part of the esophagus, Wilson-Cook prostheses (65 cases) and Sumi prostheses (51 cases) were implanted using rigid oesophagoscopy. Since 2001, 867 esophageal stents have been implanted.

RESULTS

Complications occurred in 146 (11%) patients, including 7 (0.6%) cases of death. The most common complication was the recurrence of swallowing disorders (74 patients). In 51 patients, tumor overgrowth over the stent/prosthesis was responsible for that symptom, and in 23 patients its clogging. A fistula (22 cases) and the passage of the prosthesis/stent (25 cases) were the second most common group of complications. Compression of the trachea, bleeding, and dehiscence of wounds occurred in a total of 18 patients. Complications were mostly treated through the repositioning of the prosthesis/stent or the insertion of an additional one.

CONCLUSIONS

The most common complications after esophageal prosthetics are the recurrence of dysphagia, a fistula and the displacement of the prosthesis/stent. The basic treatment of complications is the repositioning or insertion of an additional prosthesis.

In Vitro and In Vivo Assessment of Docetaxel Formulation Developed for Esophageal Stents

Esophageal cancer (EC) mostly affects the elderly population and is frequently diagnosed at an advanced stage. Self-expanding metal stents (SEMS) are the most popular mode of palliation, but they are associated with reocclusion caused by tumor growth. To overcome this problem, docetaxel (DTX)-loaded polyurethane formulations were prepared for stent application. The films were evaluated against the cancer cell lines, OE-19 and OE-21, and normal esophageal cell line Het-1A. The DTX and the formulations were evaluated in vitro for the cytotoxicity and in vivo in nude mice. It was found that DTX and the formulations have a weak activity against the EC cell lines and an even weaker activity against Het-1A cell line. Preliminary in vivo studies showed skin toxicity in nude mice necessitating modification of the formulation. Reevaluation in a mouse xenograft model resulted in toxicity at high dose formulations while the low dose formulation exhibited modest advantage over commercial IV formulation; however, there was no significant difference between the commercial IV and blank formulation. DTX combination with an anti-cancer agent having complementary mode of action and non-overlapping toxicity could yield better outcome in future.

Migrated esophageal stent posing a challenge for ventilation

Self-expandable esophageal stents are being commonly used for palliative treatment in advanced esophageal cancer patients to relieve dysphagia, prevent tracheoesophageal fistula, and facilitate symptomatic betterment. The modern covered stents reduce the ingrowth of the tumor but have seen an increase in the incidence of stent migrations. We report a rather complicated presentation of an esophageal stent for esophageal dilatation and a challenging management of a difficult tracheostomy.

Feasibility, efficacy and safety of stent insertion as a palliative treatment for malignant strictures in the cervical segment of the esophagus and the hypopharynx

BACKGROUND

50% of esophageal cancers are inoperable at the time of diagnosis, and around 15% involve the cervical esophagus. The hypopharynx is often involved by these malignancies as well. Palliation of cervical esophageal malignancies through stent insertion is considered limited due to technical challenges, poor patient tolerance and high complication rate. The aim of this study is to review our experience with stent insertion in the cervical segment of the esophagus and to evaluate outcome differences between stent insertions involving or sparing the hypopharynx.

METHODS

We retrospectively reviewed data on 69 consecutive patients that underwent stent insertion for malignant strictures in the cervical esophagus at our Department. Patients were divided according to involvement or sparing of the lower hypopharynx. Dysphagia severity was measured with the Mellow-Pinkas scale before the procedure and on monthly follow-ups. Any complication and its management were recorded. The main outcome parameters were as follows: dysphagia improvement, rate of successful dysphagia palliation (i.e., a reduction of the score to 0 or 1 after stent insertion) and complication rate. Multivariable analysis was carried out to assess the influence of patient- and procedure-related factors on the outcome of the procedure.

RESULTS

Stent insertion was achieved in 100% patients. At 4 weeks, dysphagia score improved from a median of 3-0 (p < 0.001), and a successful palliation was achieved in 76.8% patients. The 30-day mortality rate was 14.5%. Successful palliation throughout the follow-up was achieved in 72.9% of the surviving patients. Complications occurred in 31.9% patients. Dilation before stent insertion was associated with a less efficient short-term dysphagia palliation (OR 6.77, 95% CI 1.46-31.29, p = 0.02).

CONCLUSIONS

Stent insertion is a safe and effective palliative treatment for malignant cervical esophageal strictures. Results are consistent even in patients with hypopharyngeal lesions. Dilation should be avoided before stent insertion.

Tracheo-oesophageal fistula after palliative treatment of oesophageal cancer

We present a case of an 86-year-old male who presented with severe pneumonia in the context of having undergone radiotherapy and then an oesophageal stent insertion for palliation of oesophageal cancer. He was diagnosed with a tracheo-oesophageal fistula (TOF) which was successfully managed by deploying a second stent within the first stent.

Esophageal Stenting With Sutures: Time to Redefine Our Standards?

BACKGROUND AND STUDY AIMS

Migration is the most common complication of the fully covered metallic self-expanding esophageal stent (FCSEMS). Recent studies have demonstrated migration rates between 30% and 60%. The aim of this study was to determine the effect of fixation of the FCSEMS by endoscopic suturing on migration rate.

PATIENT AND METHODS

Patients who underwent stent placement for esophageal strictures and leaks over the last year were captured and reviewed retrospectively. Group A, cases, were patients who underwent suture placement and group B, controls, were patients who had stents without sutures. Basic demographics, indications, and adverse events (AEs) were collected. Kaplan-Meier analysis and Cox regression modeling were conducted to determine estimates and predictors of stent migration in patients with and without suture placement.

RESULTS

Thirty-seven patients (18 males, 48.65%), mean age 57.2 years (±16.3 y), were treated with esophageal FCSEMS. A total of 17 patients received sutures (group A) and 20 patients received stents without sutures (group B). Stent migration was noted in a total of 13 of the 37 patients (35%) [2 (11%) in group A and 11 (55%) in group B]. Using Kaplan-Meier analysis and log-rank analysis, fixation of the stent with suturing reduced the risk of migration (P=0.04). There were no AEs directly related to suture placement.

CONCLUSIONS

Anchoring of the upper flare of the FCSEMS with endoscopic sutures is technically feasible and significantly reduces stent migration rate when compared with no suturing, and is a safe procedure with very low AEs rates.

Paclitaxel or 5-fluorouracil/esophageal stent combinations as a novel approach for the treatment of esophageal cancer

Currently, esophageal cancer is rarely curable, and herein, a paclitaxel or 5-fluorouracil/esophageal stent combination (PTX or 5-FU/stent) was used to provide a new approach to treat this cancer. The PTX or 5-FU/stent was prepared by covering a nitinol stent with a bilayered polymer film that consisted of a layer of 50% PTX or 5-FU and a layer of drug-free backing. These treatment modalities were evaluated in vivo after implantation into the porcine esophagus. The percentages of the drugs that permeated from the backing layer over a period of 95 days were very small (0.61% for 5-FU), and an overwhelming majority of the PTX and the 5-FU was released from the other side of the film. During the follow-up period (120 days), the drug/stent was always maintained in the porcine esophagus, and did not show any obvious systemic or local toxicities. In contrast, this treatment had an effect on the inhibition of tissue proliferation and ulceration. In addition, the drug concentrations were highest in the esophagus compared with in the heart, liver, spleen, lung, kidney and blood (81500.0 ± 9475.2 ng/g vs. 3.9 ± 0.3 ng/mL of PTX in the plasma at 13 days). The PTX/stent and the 5-FU/stent have a dual function as both a stent and a local drug delivery device, which provides a potential treatment modality with high efficacy and non systematic toxicity for esophageal cancer.

Endoscopic palliation of advanced esophageal cancer

Esophageal cancer represents one of the most aggressive digestive tumors, with a survival rate at 5 years of only 10%. Globally, during the last three decades, there has been an increasing incidence of the esophageal cancer, approx. 400,000 new esophageal cancers being currently diagnosed annually. This represents the eighth leading cause of cancer incidence and the sixth leading cause of cancer death overall. Taking into account the population's global aging and thus, the increase in the number of patients who will not bear surgery, PCT and radiation, or the fact that they do not want it especially because of deficiencies and associated pathology, the endoscopic ablative techniques with palliation purposes represent the alternative. If we refer to the Western Europe countries and North America, we notice an increase of esophageal adenocarcinoma rate versus squamous cancer. As for the Asian region, referring in particular to China and Japan, 9 out of 10 esophageal cancers are squamous cell carcinomas. For at least half of the patients with EC (esophageal cancer) there is no hope of healing because of the advanced regional malignant invasion (T3-4, N+, M+) with no chemo and radiotherapy response, poor preoperative patients' conditions or systemic metastasis. The low life expectancy does not justify the risky medical procedures, the goal of the therapy consisting in the improvement of the quality of life by eliminating dysphagia (reestablishing oral feeding) which represents the most common complication of EC, the respiratory tract complication caused by eso-tracheal fistulas or by eliminating chest pain. To treat dysphagia, which is the main target of palliation, combined methods like endoscopic, chemo and radio-therapy, can be used, each one with indications, benefits and risks.

Paclitaxel-eluting nanofiber-covered self-expanding nonvascular stent for palliative chemotherapy of gastrointestinal cancer and its related stenosis

Self-expanding non-vascular metal stents (SEMS) is now a choice of treatment for tumor-induced obstructive symptoms of gastrointestinal tract. But in-growing tumor causes re-stenosis. Here, we studied a paclitaxel-eluting nanofiber-covered stent for palliative chemotherapy of gastrointestinal cancer and its related stenosis. In vivo and in vitro feasibility of nanofiber-covered nonvascular stent was evaluated in this study. Nanofiber-covered stent released paclitaxel (PTX) in controlled manner for 30 days. PTX-NFM significantly inhibited the growth of CT-26 colon cancer in comparison with PTX injection. PTX maintained higher tumor concentrations over 1.0 μg/ml for more than 14 days without systemic exposure. TUNEL and H&E staining proved locally concentrated PTX induced the higher apoptosis than PTX injection. In this way, PTX-eluting nanofiber-covered stent possibly inhibits in-growth of cancer and extends patency of stent. Clinical feasibility of PTX-eluting nanofiber nonvascular stent for cholangiocarcinoma and gastrointestinal cancers will be investigated in further studies.

Polymeric photosensitizer-embedded self-expanding metal stent for repeatable endoscopic photodynamic therapy of cholangiocarcinoma

Photodynamic therapy (PDT) is a new therapeutic approach for the palliative treatment of malignant bile duct obstruction. In this study, we designed photosensitizer-embedded self-expanding nonvascular metal stent (PDT-stent) which allows repeatable photodynamic treatment of cholangiocarcinoma without systemic injection of photosensitizer. Polymeric photosensitizer (pullulan acetate-conjugated pheophorbide A; PPA) was incorporated in self-expanding nonvascular metal stent. Residence of PPA in the stent was estimated in buffer solution and subcutaneous implantation on mouse. Photodynamic activity of PDT-stent was evaluated through laserexposure on stent-layered tumor cell lines, HCT-116 tumor-xenograft mouse models and endoscopic intervention of PDT-stent on bile duct of mini pigs. Photo-fluorescence imaging of the PDT-stent demonstrated homogeneous embedding of polymeric Pheo-A (PPA) on stent membrane. PDT-stent sustained its photodynamic activities at least for 2 month. And which implies repeatable endoscopic PDT is possible after stent emplacement. The PDT-stent after light exposure successfully generated cytotoxic singlet oxygen in the surrounding tissues, inducing apoptotic degradation of tumor cells and regression of xenograft tumors on mouse models. Endoscopic biliary in-stent photodynamic treatments on minipigs also suggested the potential efficacy of PDT-stent on cholangiocarcinoma. In vivo and in vitro studies revealed our PDT-stent, allows repeatable endoscopic biliary PDT, has the potential for the combination therapy (stent plus PDT) of cholangiocarcinoma.

Esophageal stent fracture: Case report and review of the literature

Endoscopic esophageal stent placement is widely used in the treatment of a variety of benign and malignant esophageal conditions. Self expanding metal stents (SEMS) are associated with significantly reduced stent related mortality and morbidity compared to plastic stents for treatment of esophageal conditions; however they have known complications of stent migration, stent occlusion, tumor ingrowth, stricture formation, reflux, bleeding and perforation amongst others. A rare and infrequently reported complication of SEMS is stent fracture and subsequent migration of the broken pieces. There have only been a handful of published case reports describing this problem. In this report we describe a case of a spontaneously fractured nitinol esophageal SEMS, and review the available literature on the unusual occurrence of SEMS fracture placed for benign or malignant obstruction in the esophagus. SEMS fracture could be a potentially dangerous event and should be considered in a patient having recurrent dysphagia despite successful placement of an esophageal SEMS. It usually requires endoscopic therapy and may unfortunately require surgery for retrieval of a distally migrated fragment. Early recognition and prompt management may be able to prevent further problems.

A comprehensive review of esophageal stents

Esophageal stents are important tools for palliative treatment of inoperable esophageal malignancies. With the development of multiple self-expandable stents, there are now several therapeutic options for managing benign and malignant esophageal diseases. This paper discusses the various types of esophageal stents currently available, indications for their placement, challenges and complications that gastroenterologists face when placing these stents, and some of the innovations that will become available in the near future.