Clinical application of iodine-eluting stent in patients with advanced esophageal cancer

A Functional Stent Encapsulating Radionuclide in Temperature-Memory Spiral Tubes for Malignant Stenosis of Esophageal Cancer

Stent implantation is a commonly used palliative treatment for alleviating stenosis in advanced esophageal cancer. However, tissue proliferation induced by stent implantation and continuous tumor growth can easily lead to restenosis. Therefore, functional stents are required to relieve stenosis while inhibiting tissue proliferation and tumor growth, thereby extending the patency. Currently, no ideal functional stents are available. Here, iodine-125 (125 I) nuclides are encapsulated into a nickel-titanium alloy (NiTi) tube to develop a novel temperature-memory spiral radionuclide stent (TSRS). It has the characteristics of temperature-memory, no cold regions at the end of the stent, and a uniform spatial dose distribution. Cell-viability experiments reveal that the TSRS can reduce the proliferation of fibroblasts and tumor cells. TSRS implantation is feasible and safe, has no significant systemic radiotoxicity, and can inhibit in-stent and edge stenosis caused by stent-induced tissue proliferation in healthy rabbits. Moreover, TSRS can improve malignant stenosis and luminal patency resulting from continuous tumor growth in a VX2 esophageal cancer model. As a functional stent, the TSRS combines the excellent properties of NiTi with brachytherapy of the 125 I nuclide and will make significant contributions to the treatment of malignant esophageal stenosis.

Radiotherapy for Advanced Esophageal Cancer: from Palliation to Curation

OPINION STATEMENT

Esophageal cancer is a global health problem, which is 7th most common and 6th most deadly cancer. It has been the era of immuno-oncology for esophageal cancer management. Radiation therapy has been one of the key local therapeutic approaches for esophageal cancer treatment, while its role in advanced disease is challenging and debatable. There have been emerging clinical and translational studies of radiation therapy in recurrent or metastatic esophageal cancer. Immunotherapy has been established the standard care of 1st and 2nd line systemic therapies of advanced esophageal cancer, and the development of tumor immunity has opened a new chapter for the esophageal cancer radiation therapy. The current review will summarize the classic radiation therapy research in advanced esophageal cancer, as well as the most recent key findings. The subtitles will cover palliative radiotherapy for dysphagia, re-radiation for recurrent disease, oligo-focal disease management and stereotactic radiation therapy, and radiotherapy with immunotherapy. Radiotherapy plays vital role in multidisciplinary management of advanced EC. External or intratumoral irradiation has been used for palliation of dysphagia and improving QOL in esophageal cancer patients traditionally, while recent clinical and technical advance enables radiotherapy to be considered in recurrent or metastatic disease for curation attention. Novel clinical and translational investigation is opening a new chapter of radiotherapy with immunotherapy for benefiting advanced EC patients.

Utilizing 4D Printing to Design Smart Gastroretentive, Esophageal, and Intravesical Drug Delivery Systems

The breakthrough of 3D printing in biomedical research has paved the way for the next evolutionary step referred to as four dimensional (4D) printing. This new concept utilizes the time as the fourth dimension in addition to the x, y, and z axes with the idea to change the configuration of a printed construct with time usually in response to an external stimulus. This can be attained through the incorporation of smart materials or through a preset smart design. The 4D printed constructs may be designed to exhibit expandability, flexibility, self-folding, self-repair or deformability. This review focuses on 4D printed devices for gastroretentive, esophageal, and intravesical delivery. The currently unmet needs and challenges for these application sites are tried to be defined and reported on published solution concepts involving 4D printing. In addition, other promising application sites that may similarly benefit from 4D printing approaches such as tracheal and intrauterine drug delivery are proposed.

Dosimetric Evaluation and Clinical Application of Radioactive Iodine-125 Brachytherapy Stent in the Treatment of Malignant Esophageal Obstruction

Objective

To evaluate the dosimetric characteristics and the clinical application of radioactive iodine-125 brachytherapy stent (RIBS) in malignant esophageal obstruction.

Methods

The dose distribution of RIBS with different seed spacing, diameter and length was studied by treatment planning system (TPS) calculation, thermoluminescence dosimeter (TLD) measurement and Monte Carlo (MC) data fitting. And the data of esophageal cancer patients who were treat with this type of RIBS was analyzed retrospectively.

Results

Doses around the RIBS calculated by the TPS lay between those measured by the TLDs and those simulated by the MC, and the differences between the three methods were significant (p<0.05), the overall absolute dose differences among the three methods were small. Dose coverage at 1.5 cm from the center was comprehensive when the activity reached 0.6 mCi. Both the conformability and the uniformity of isodose lines produced by a seed spacing of 1.0 cm were superior to those produced by a seed spacing of 1.5 cm. The data of 50 patients treated with RIBS was analyzed. They were followed up until February 2020 when all of the patients died. The overall improvement rate of dysphagia after RIBS implant was 90%. Moderate and severe complications with an incidence of more than 10% were hematemesis (28%), pain (20%), and lung infection (10%). Stent restenosis occurred in 4 patients at a median interval of 108 days from the procedure. The overall incidence of fatal complications was 38% (including hematemesis, infection and asphyxia). The median survival time of patients with and without a history of radiotherapy were 3.4 months and 6 months, respectively, the difference of which was significant (p=0.021). No other factors affecting survival were identified. For patients with and without a history of radiotherapy, the incidences of fatal complications were 51.7% and 19%, respectively (p=0.019). No correlation between dose and stent restenosis was found.

Conclusion

TPS calculations are suitable for clinical applications. RIBS can effectively alleviate obstructive symptoms for patients with malignant esophageal obstruction, but the incidence of fatal complications was high, care should be taken when choosing this treatment.

I-125 seed-loaded versus normal stent insertion for obstructive esophageal cancer: a meta-analysis

Introduction

Malignant esophageal obstruction is usually caused by esophageal and other chest cancers. More than 80% of cases of obstructive esophageal cancer (OEC) have lost the chance of curative resection. Stent insertion is a first-line palliative approach used to treat incurable OEC.

Aim

To gauge the relative clinical efficacy of I-125 seed-loaded stent (ISS) versus normal stent (NS) insertion as a treatment for OEC.

Material and methods

Querying of the PubMed, Embase, and Cochrane Library databases was conducted to find all relevant studies published up to November 2020. The meta-analysis was undertaken using RevMan v5.3.

Results

We identified 158 studies initially, eight (4 randomized controlled trials and 4 retrospective studies) of which were used in this meta-analysis. We found that the two groups exhibited the comparable pooled Δdysphagia scores (MD = 0.02; p = 0.80), stent restenosis rates (OR = 0.97; p = 0.89), stent migration rates (OR = 0.81; p = 0.63), severe chest pain rates (OR = 1.05; p = 0.81), hemorrhage rates (OR = 1.53; p = 0.16), aspiration pneumonia rates (OR = 0.72; p = 0.38), and fistula formation rates (OR = 1.47; p = 0.44). The pooled time-to-restenosis and survival were both significantly longer in the ISS group (p = 0.04 and < 0.0001, respectively). Significant heterogeneity was detected in the endpoints of Δdysphagia scores and survival (I² = 73% and 86%, respectively). Funnel plot analysis indicated an absence of publication bias related to the selected study endpoints.

Conclusions

For patients with OEC, our meta-analysis indicated that ISS insertion could provide longer stent patency and survival than NS insertion.

Meta-analysis of efficacy and complications of intraluminal radioactive stent and common covered stent in treatment of advanced esophageal cancer

BACKGROUND

The main symptom of advanced esophageal cancer is dysphagia. Because there is no indication for surgery, in order to improve the patient's symptoms and quality of life, esophageal stent therapy has become the main palliative treatment. Based on the results of many studies, it can be speculated that intraluminal radioactive stent is better since it combines the function of ordinary stent and brachytherapy.

AIM

To evaluate the difference in the curative effect and complications between intraluminal radioactive stent (iodine 125 particle scaffold) and common covered stent in patients with mid-advanced esophageal cancer.

METHODS

A computer search of the electronic databases PubMed (1989/2020-03), Web of Science (2000/2020-03), Wiley Online Library (1992/2020-03), CNKI database (1978/2020-03), Wanfang database (1997/2020-03), and VIP database (2000/2020-03) and a manual search of Cochrance library were performed to retrieve articles using the method recommended by the Cochrance System Evaluator's Manual (version 4.2.2). The Oxford's 2011 evidence level assessment was used to evaluate the quality of the included articles, and Meta-analysis was performed using Revman 5.3 software.

RESULTS

Ten articles were finally included, with a total of 943 patients involved. Among the patients, 449 were implanted with an intraluminal radioactive stent and 494 were implanted with a common covered stent. A meta-analysis of 10 articles showed that the average survival time of the intraluminal radioactive stent group was 3.91 mo longer than that of the common covered stent group (95%CI: 1.68-6.13, Z = 3.44, P = 0.0006), and the median survival time was 3.12 mo longer 95%CI: 1.78-4.47, Z = 4.57, P = 0.0001). The dysphagia scores of the two groups of patients were significantly reduced within 1 and 3 mo after the stent was placed (P < 0.05), but there was no statistical difference between the two groups (P > 0.05). After stenting, there was no statistically significant difference in the incidence of pain (odds ratio [OR] = 0.89, 95%CI: 0.65-1.21, Z = 0.77, P = 0.44), bleeding (OR = 0.80, 95%CI: 0.52-1.22, Z = 1.03, P = 0.30), perforation (OR = 1.16, 95%CI: 0.55-2.43, Z = 0.39, P = 0.70), or stent displacement (R = 0.66, 95%CI: 0.31-1.38, Z = 1.10, P = 0.27) between the intraluminal radioactive stent group and the common covered stent group; but there was a statistical difference in the incidence of restenosis [OR = 0.61 , 95%CI (0.42-0.87), Z = 3.73 P = 0.006] between them.

CONCLUSION

The use of intraluminal radioactive stent in the treatment of advanced esophageal cancer can prolong the average survival time and median survival time of patients, and signficantly reduce the incidence of restenosis after surgery; however, the two types of stents have no significant difference in relieving the symptoms of dysphagia within 1-3 mo or in reducing postoperative complications such as pain, hemorrhage, perforation, and stent displacement.

Influence of Polymer Composition on the Controlled Release of Docetaxel: A Comparison of Non-Degradable Polymer Films for Oesophageal Drug-Eluting Stents

Following the huge clinical success of drug-eluting vascular stents, there is a significant interest in the development of drug-eluting stents for other applications, such as the treatment of gastrointestinal (GI) cancers. Central to this process is understanding how particular drugs are released from stent coatings, which to a large extent is controlled by drug-polymer interactions. Therefore, in this study we investigated the release of docetaxel (DTX) from a selection of non-degradable polymer films. DTX-polymer films were prepared at various loadings (1, 5 and 10% w/w) using three commercially available polymers including poly(dimethylsiloxane) (PSi), poly (ethylene-co-vinyl acetate) (PEVA) and Chronosil polyurethane (PU). The formulations were characterised using different techniques such as photoacoustic Fourier-transform infrared (PA-FTIR) spectrophotometry, X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The effect of DTX on the mechanical properties of the films, in-vitro release, and degradation tests were also assessed. For all polymers and DTX loadings, the drug was found to disperse homogenously without crystallisation within the polymer matrix. While no specific interactions were observed between DTX and PSi or PEVA, hydrogen-bonding appeared to be present between DTX and PU, which resulted in a concentration-dependent decrease in the Young’s moduli of the films due to disruption of inter-polymeric molecular interactions. In addition, the DTX-PU interactions were found to modulate drug release, providing near-linear release over 30 days, which was accompanied by a significant reduction in degradation products. The results indicate that DTX-loaded PU films are excellent candidates for drug-eluting stents for the treatment of oesophageal cancer.

Three-dimensional printed 5-fluorouracil eluting polyurethane stents for the treatment of oesophageal cancers

3D printing is introduced as rapid and facile approach to prepare personalized drug-eluting stents for the treatment of oesophageal cancers.

Treatment for unresectable or metastatic oesophageal cancer: current evidence and trends

Approximately half of the patients diagnosed with oesophageal cancer present with unresectable or metastatic disease. Treatment for these patients aims to control dysphagia and other cancer-related symptoms, improve quality of life and prolong survival. In the past 25 years, modestly improved outcomes have been achieved in the treatment of patients with inoperable non-metastatic cancer who are medically not fit for surgery or have unresectable, locally advanced disease. Concurrent chemoradiotherapy offers the best outcomes in these patients. In distant metastatic oesophageal cancer, several double-agent or triple-agent chemotherapy regimens have been established as first-line treatment options. In addition, long-term results of multiple large randomized phase III trials using additional targeted therapies have been published in the past few years, affecting contemporary clinical practice and future research directions. For the local treatment of malignant dysphagia, various treatment options have emerged, and self-expandable metal stent (SEMS) placement is currently the most widely applied method. Besides the continuous search for improved SEMS designs to minimize the risk of associated complications, efforts have been made to develop and evaluate the efficacy of antireflux stents and irradiation stents. This Review outlines the current evidence and ongoing trends in the different modern-day, multidisciplinary interventions for patients with unresectable or metastatic oesophageal cancer with an emphasis on key randomized trials.

Radioactive self-expanding stents for palliative management of unresectable esophageal cancer: a systematic review and meta-analysis

Stent insertion is a feasible and safe palliative management for advanced unresectable esophageal cancer. The aim of this study is to assess the efficacy of radioactive stent for unresectable esophageal cancer compared with conventional stent. Systematic searches of the PubMed and Web of science are dated from their beginning to January 25, 2016. Studies that compared radioactive stent with conventional stent for unresectable esophageal cancer were included. The outcomes were postimplantation survival, relief of dysphagia, and complications related to stent implant. Six studies with 539 patients were included. All of them used stent equipped with radioactive iodine beads as a radioactive stent. The pooled weighted mean difference for median survival was 2.734 months (95% CI 1.710-3.775; Z = 5.21, P = 0.000) between two groups. The 1,3,6 month survival rates were higher in radioactive stents than conventional stent, with the pooled ORs 3.216 (95% CI 1.293-7.999; Z = 2.51, P = 0.012), 3.095 (95% CI 1.908-5.020; Z = 4.58, P = 0.000), and 7.503 (95% CI 2.206- 25.516; Z = 3.23, P = 0.001, respectively). The pooled hazard ratio was 0.464 (95% CI 0.328-0.655; Z = 4.35, P = 0.000) between two groups. For relief of dysphagia, two stents all have good relief of the dysphagia effect, but radioactive stent showed a better effect at 3, 6 months follow-up after implantation. For complications related to stent implant, no significant differences were found between two stents in terms of severe chest pain (30.0% vs. 35.7%, OR 0.765, 95% CI 0.490-1.196), gastroesophageal reflux (18.6% vs. 16.1%, OR 1.188, 95% CI 0.453-3.115), fever (12.1% vs. 12.1%, OR 1.014, 95% CI 0.332-3.097), bleeding (16.7% vs. 14.2%, OR 1.201, 95% CI 0.645-2.236), perforation or fistula (6.1% vs. 9.0%, OR 0.658, 95% CI 0.291-1.486), pneumonia (10.7% vs. 14.1%, OR 0.724, 95% CI 0.343-1.526), stent migration (7.0% vs. 10.2%, OR 0.651, 95% CI 0.220-1.924), and restenosis (24.2% vs. 20.6%, OR 1.228, 95% CI 0.674-2.239). Radioactive stent insertion had potential benefits for palliative management for patients with unresectable esophageal cancer. This method prolonged survival and dysphagia relief period without more complications. However, this conclusion should be confirmed by more trials.

Comparative study of self-expanding metal stent and intraluminal radioactive stent for inoperable esophageal squamous cell carcinoma

BACKGROUND

We compared the effectiveness of self-expanding metal stent alone vs. radioactive stent embedded with 125I seeds implantation insertion in patients of inoperable esophageal squamous cell cancer combined with malignant esophageal stenosis.

METHODS

We studied two groups of patients with stenosis attribute to inoperable esophageal squamous cell carcinoma. Group A had placed self-expanding metal stent alone insertion; group B encountered radioactive stent embedded with 125I seeds. Patients were followed up by monthly home visits or telephone interview. Survival time was analyzed with Kaplan-Meier analysis. Log rank test was used to analyze factors of survival time for all significant differences.

RESULTS

There was no significant difference between the two groups of all baseline characteristics. There was no statistical difference in complications including massive hematemesis, pain more than 1 month, stent migration, and restenosis. Survival time and causes of death such as tumor metastasis, massive hemorrhage, non-tumor-related factors, and restenosis were comparable between the two groups (P>0.05). The medical costs were significantly less in group A than those in group B (P<0.01).

CONCLUSIONS

Radioactive stent embedded with (125)I seeds was not significant in improving survival rate, but showed to increase hospitalization costs compared to self-expandable metal stent alone in treating inoperable esophageal squamous cell carcinoma stricture.

Interventions for dysphagia in oesophageal cancer

BACKGROUND

Most patients with oesophageal and gastro-oesophageal carcinoma are diagnosed at an advanced stage and require palliative intervention. Although there are many kinds of interventions, the optimal one for the palliation of dysphagia remains unclear. This review updates the previous version published in 2009.

OBJECTIVES

The aim of this review was to systematically analyse and summarise the efficacy of different interventions used in the palliation of dysphagia in primary oesophageal and gastro-oesophageal carcinoma.

SEARCH METHODS

To find new studies for this updated review, in January 2014 we searched, according to the Cochrane Upper Gastrointestinal and Pancreatic Diseases model, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and CINAHL; and major conference proceedings (up to January 2014).

SELECTION CRITERIA

Only randomised controlled trials (RCTs) were included in which patients with inoperable or unresectable primary oesophageal cancer underwent palliative treatment. Different interventions like rigid plastic intubation, self-expanding metallic stent (SEMS) insertion, brachytherapy, external beam radiotherapy, chemotherapy, oesophageal bypass surgery, chemical and thermal ablation therapy, either head-to-head or in combination, were included. The primary outcome was dysphagia improvement. Secondary outcomes included recurrent dysphagia, technical success, procedure related mortality, 30-day mortality, adverse effects and quality of life.

DATA COLLECTION AND ANALYSIS

Data collection and analysis were performed in accordance with the methods of the Cochrane Upper Gastrointestinal and Pancreatic Diseases Review Group.

MAIN RESULTS

We included 3684 patients from 53 studies. SEMS insertion was safer and more effective than plastic tube insertion. Thermal and chemical ablative therapy provided comparable dysphagia palliation but had an increased requirement for re-interventions and for adverse effects. Anti-reflux stents provided comparable dysphagia palliation to conventional metal stents. Some anti-reflux stents might have reduced gastro-oesophageal reflux and complications. Newly-designed double-layered nitinol (Niti-S) stents were preferable due to longer survival time and fewer complications compared to simple Niti-S stents. Brachytherapy might be a suitable alternative to SEMS in providing a survival advantage and possibly a better quality of life, and might provide better results when combined with argon plasma coagulation or external beam radiation therapy.

AUTHORS' CONCLUSIONS

Self-expanding metal stent insertion is safe, effective and quicker in palliating dysphagia compared to other modalities. However, high-dose intraluminal brachytherapy is a suitable alternative and might provide additional survival benefit with a better quality of life. Some anti-reflux stents and newly-designed stents lead to longer survival and fewer complications compared to conventional stents. Combinations of brachytherapy with self-expanding metal stent insertion or radiotherapy are preferable due to the reduced requirement for re-interventions. Rigid plastic tube insertion, dilatation alone or in combination with other modalities, and chemotherapy alone are not recommended for palliation of dysphagia due to a high incidence of delayed complications and recurrent dysphagia.

Conventional stents versus stents loaded with (125)iodine seeds for the treatment of unresectable oesophageal cancer: a multicentre, randomised phase 3 trial

BACKGROUND

The combination of stent insertion and single high-dose brachytherapy is a feasible and safe palliative treatment regimen in patients with unresectable oesophageal cancer. We aimed to further assess the efficacy of this treatment strategy compared to a conventional covered stent in patients with dysphagia caused by unresectable oesophageal cancer.

METHODS

In this multicentre, single-blind, randomised, phase 3 trial, we enrolled patients with unresectable oesophageal cancer from 16 hospitals in China. We included adult patients (aged ≥ 20 years) with progressive dysphagia, unresectable tumours due to extensive lesions, metastases, or poor medical condition, and with clear consciousness, cooperation, and an Eastern Cooperative Oncology Group (ECOG) performance status score of 0-3. Eligible patients were randomly assigned (in 1:1 ratio, no stratification) to receive either a stent loaded with (125)iodine radioactive seeds (irradiation group) or a conventional oesophageal stent (control group). The primary endpoint was overall survival. Survival analyses were done in a modified intention-to-treat group. This study is registered with ClinicalTrials.gov, number NCT01054274.

FINDINGS

Between Nov 1, 2009, and Oct 31, 2012, 160 patients were randomly assigned to receive treatment with either an irradiation stent (n=80) or a conventional stent (n=80). During a median follow-up of 138 days (IQR 72-207), 148 stents (73 in the irradiation group and 75 in the control group) were successfully placed into the diseased oesophagus in 148 participants. Median overall survival was 177 days (95% CI 153-201) in the irradiation group versus 147 days (124-170) in the control group (p=0.0046). Major complications and side-effects of the treatment were severe chest pain (17 [23%] of 73 patients in the irradiation group vs 15 [20%] of 75 patents in the control group), fistula formation (six [8%] vs five [7%]), aspiration pneumonia (11 [15%] vs 14 [19%]), haemorrhage (five [7%] vs five [7%]), and recurrent dysphagia (21 [28%] vs 20 [27%]).

INTERPRETATION

In patients with unresectable oesophageal cancer, the insertion of an oesophageal stent loaded with (125)iodine seeds prolonged survival when compared with the insertion of a conventional covered self-expandable metallic stent.