Therapeutic bronchoscopy for malignant central airway obstruction: Introduction to the EpiGETIF registry

BACKGROUND AND OBJECTIVE

EpiGETIF is a web-based, multicentre clinical database created in 2019 aiming for prospective collection of data regarding therapeutic rigid bronchoscopy (TB) for malignant central airway obstruction (MCAO).

METHODS

Patients were enrolled into the registry from January 2019 to November 2022. Data were prospectively entered through a web-interface, using standardized definitions for each item. The objective of this first extraction of data was to describe the population and the techniques used among the included centres to target, facilitate and encourage further studies in TB.

RESULTS

Overall, 2118 patients from 36 centres were included. Patients were on average 63.7 years old, mostly male and smokers. Most patients had a WHO score ≤2 (70.2%) and 39.6% required preoperative oxygen support, including mechanical ventilation in 6.7%. 62.4% had an already known histologic diagnosis but only 46.3% had received any oncologic treatment. Most tumours were bronchogenic (60.6%), causing mainly intrinsic or mixed obstruction (43.3% and 41.5%, respectively). Mechanical debulking was the most frequent technique (67.3%), while laser (9.8%) and cryo-recanalization (2.7%) use depended on local expertise. Stenting was required in 54.7%, silicone being the main type of stent used (55.3%). 96.3% of procedure results were considered at least partially successful, resulting in a mean 4.1 points decrease on the Borg scale of dyspnoea. Complications were noted in 10.9%.

CONCLUSION

This study exposes a high volume of TB that could represent a good source of future studies given the dismal amount of data about the effects of TB in certain populations and situations.

World Association for Bronchology and Interventional Pulmonology (WABIP) guidelines on airway stenting for malignant central airway obstruction

Malignant Central Airway Obstruction (MCAO) encompasses significant and symptomatic narrowing of the central airways that can occur due to primary lung cancer or metastatic disease. Therapeutic bronchoscopy is associated with high technical success and symptomatic relief and includes a wide range of airway interventions including airway stents. Published literature suggests that stenting practices vary significantly across the world primarily due to lack of guidance. This document aims to address this knowledge gap by addressing relevant questions related to airway stenting in MCAO. An international group of 17 experts from 17 institutions across 11 countries with experience in using airway stenting for MCAO was convened as part of this guideline statement through the World Association for Bronchology and Interventional Pulmonology (WABIP). We performed a literature and internet search for reports addressing six clinically relevant questions. This guideline statement, consisting of recommendations addressing these six PICO questions, was formulated by a systematic and rigorous process involving the evaluation of published evidence, augmented with expert experience when necessary. Panel members participated in the development of the final recommendations using the modified Delphi technique.

Predictors in the treatment of malignant central airway obstruction with silicone stents

PURPOSE

To examine the role of the silicone stent in palliation of malignant central airway obstruction and identify potential preprocedural predictors for postprocedural outcome.

METHODS

Patients treated with endoscopic insertion of tracheobronchial silicone stents for malignant central airway obstruction at Aarhus University Hospital from 2012 to 2022 were identified from electronic medical records. Statistical analyses were carried out to identify factors affecting Days Alive and Out of Hospital, complications and overall survival.

RESULTS

81 patients underwent a total of 90 tracheobronchial stent insertions. Days Alive and Out of Hospital (DAOH) for the first 30 days were affected negatively by urgent intervention, p < 0.001, preprocedural non-invasive respiratory support, p < 0.001, and preprocedural intubation, p = 0.02. Post-procedural oncological treatment was associated with a significant improved DAOH, p = 0.04. Symptomatology and lesion characteristics were not significantly associated with any impact on DAOH. Overall survival was poor (mean survival was 158 days), and only significantly affected by severe degree of dyspnea, p = 0.02, and postprocedural oncological treatment, p < 0.001. Complication where registered in 25.6% of cases within the first 30 days was observed. Procedure-related mortality was 3.7%. Based on chart annotations by an ENT-surgeon, 95% of the patients experienced relief of symptoms following stent insertion.

CONCLUSIONS

Palliative tracheobronchial airway stenting with silicone stents is found to have a beneficial impact, more research is required for identification of predictors for postprocedural outcome based on preprocedural classifications.

Tracheobronchial stents: an expanding prospect

The first dedicated tracheobronchial silicone stent was designed by the French pulmonologist Jean-Paul Dumon. The most common indications for stenting are to minimise extrinsic airway compression from mass effect, maintain airway patency due to intrinsic obstruction or treat significant nonmalignant airway narrowing or fistulae. Silicone stents require rigid bronchoscopy for insertion; however, they are more readily repositioned and removed compared with metallic stents. Metallic stents demonstrate luminal narrowing when loads are applied to their ends, therefore stents should either be reinforced at the ends or exceed the area of stenosis by a minimum of 5 mm. Nitinol, a nickel-titanium metal alloy, is currently the preferred material used for airway stents. Airway stenting provides effective palliation for patients with severe symptomatic obstruction. Drug-eluting and three-dimensional printing of airway stents present promising solutions to the challenges of the physical and anatomical constraints of the tracheobronchial tree. Biodegradable stents could also be a solution for the treatment of nonmalignant airway obstruction.

Malignant Airway Obstruction and Endobronchial Stent Placement: A Systematic Review on the Efficacy and Safety

The systematic review aims to evaluate the efficacy and safety of endobronchial stent placement for malignant airway obstruction.  A comprehensive search was conducted across multiple databases to identify relevant studies. Cohort studies, randomized controlled trials, and case-control studies examining the outcomes of endobronchial stent placement in patients with malignant airway obstruction were included. Data on pre-treatment evaluation, such as pulmonary function testing, dyspnea severity scoring systems, arterial blood gas parameters, imaging, and degree of obstruction, were also collected. Primary outcomes of interest included post-procedure stenosis, pulmonary function testing evaluation, blood gas parameters, and survival outcomes. Secondary outcomes encompassed improvements in clinical status, dyspnea grade, and procedure-related complications. A total of 27 studies met the inclusion criteria and were included in the systematic review. The included studies demonstrated promising outcomes of endobronchial stent placement in managing malignant airway obstruction. Post-procedure airway diameters, pulmonary function testing, and blood gas parameters improved significantly. Survival outcomes varied among studies. Furthermore, endobronchial stent placement was associated with improvements in clinical status and dyspnea grade. Procedure-related complications ranged from pain, hemoptysis and mucus plugging to stent obstruction, migration and pneumothorax.  This systematic review suggests that endobronchial stent placement is an effective and safe intervention for managing malignant airway obstruction. It offers significant improvements in post-procedure stenosis, pulmonary function testing, blood gas parameters, and clinical outcomes. However, further studies with larger sample sizes and standardized reporting are warranted to better evaluate the long-term efficacy and safety of endobronchial stent placement for malignant airway obstruction.

[Non-infectious respiratory emergencies in patients with cancer]

Patients with a solid tumor or hematologic malignancy are often addressed to emergency units for an acute respiratory complication associated with the underlying cancer or secondary to treatments. The current article is part of a thematic series: "Intensive care and emergencies in solid tumours and blood cancer patients" and will develop the following points: (1) malignant proximal airway obstruction and, more specifically, the role of therapeutic bronchoscopy; (2) superior vena cava syndrome by tumor compression and/or secondary to thrombosis (diagnosis, local and systemic treatments); (3) cancer-related pulmonary embolism (incidence, indications for low-molecular weight heparins and direct oral anticoagulants). Other respiratory emergencies will be dealt in the other articles of this series.

Forbearance with endobronchial stenting: cognisance before conviction

Endobronchial stenting is an important aspect of the practice of interventional pulmonology. The most common indication for stenting is the management of clinically significant airway stenosis. The list of endobronchial stents available on the market continues to grow. More recently, patient-specific 3D-printed airway stents have been approved for use. Airway stenting should be considered only when all other options have been exhausted. Due to the environment of the airways and the stent-airway wall interactions, stent-related complications are common. Although stents can be placed in various clinical scenarios, they should only be placed in scenarios with proven clinical benefit. The unwarranted placement of a stent can expose the patient to complications with little or no clinical benefit. This article reviews and outlines the key principles of endobronchial stenting and important clinical scenarios in which stenting should be avoided.

[Bronchoscopic management of malignant central airway obstructions]

Up to 30% of lung cancer patients suffer from central airway obstruction, resulting in major deterioration in prognosis and quality of life. Interventional bronchoscopy combines a number of invasive techniques used during rigid bronchoscopy. It is designed to rapidly improve symptoms, primarily dyspnea. Applied according to very precise indications, this technique requires careful patient selection and needs to be incorporated into the multimodal oncological management in combination with systemic treatments, radiation therapy and surgery.

Fatal Stent-Associated Respiratory Tract Infection Caused by K64-ST11 KPC-2-Producing Carbapenem-Resistant Hypervirulent Klebsiella pneumoniae: A Rare Case Report

Objectives: This study reported a fatal stent-associated respiratory tract infection (SARTI) caused by carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP). Case: A bare-metal stent in the left main bronchus and a Y-shaped stent graft in the tracheal bronchus were placed successively in a 50-year-old woman due to shortness of breath after undergoing multiple chemotherapy treatments for lung cancer. Unfortunately, the followed SARTI and lung abscess in our patient caused by CR-hvKP eventually led to the death of the patient, despite our aggressive clearing of phlegm and potent antibiotics. The genomic analysis showed it was caused by a KPC-2-producing extensively drug-resistant K64-ST11 hypervirulent K. pneumoniae harboring several virulence and antimicrobial resistance genes. Conclusion: This study highlights the risk of SARTI caused by CR-hvKP in immunocompromised individuals.

Malignant Central Airway Obstruction: What's New?

Malignant central airway obstruction (MCAO) is a debilitating and life-limiting complication that occurs in an unfortunately large number of individuals with advanced intrathoracic cancer. Although the management of MCAO is multimodal and interdisciplinary, the task of providing patients with prompt palliation falls increasingly on the shoulders of interventional pulmonologists. While a variety of tools and techniques are available for the management of malignant obstructive lesions, advancements and evolution in this therapeutic venue have been somewhat sluggish and limited when compared with other branches of interventional pulmonary medicine (e.g., the early diagnosis of peripheral lung nodules). Indeed, one pragmatic, albeit somewhat uncharitable, reading of this article's title might suggest a wry smile and shug of the shoulders as to imply that relatively little has changed in recent years. That said, the spectrum of interventions for MCAO continues to expand, even if at a less impressive clip. Herein, we present on MCAO and its endoscopic and nonendoscopic management-that which is old, that which is new, and that which is still on the horizon.

[Bronchoscopic treatment of malignant central airway obstruction: A cohort study, long-term survival and complications]

INTRODUCTION

Interventional bronchoscopy is now the standard treatment for tracheobronchial narrowing due to tumor. The objective of our study was to analyze long-term survival and complications occurring in patients with malignant airway obstruction.

METHODS

We retrospectively studied the data from 93 patients treated between 2008 and 2019.

RESULTS

One hundred and eleven therapeutic bronchoscopies were performed. Sixty-seven patients had primary lung cancer, in 17 had tumors of another origin and 9 patients had benign or local lung tumors. Thulium laser was frequently used prior to tumor enucleation and to restore hemostasis. Seventy-one silicone stents were inserted. The death rate at the time of the procedure was 1.8% and immediate complication occurred in 9.9% of the patients. Long-term survival was significantly better for patients with cancer from other origins than in those with primary lung cancer (615.5days versus 177.9days). On the other hand, there was no significant difference in long-term survival between patients with locally advanced and metastatic lung cancer with endobronchial lesions treated by stent and those who were not (234.2days versus 164.6days). All patients with benign or with locally malignant tumors were still alive.

CONCLUSION

Therapeutic bronchoscopy increases the long-term survival of patients with malignant airway obstruction. The risk-benefit ratio was favorable.

Central airway obstruction treatment with self-expanding covered Y-carina nitinol stents: A single center retrospective analysis

Background

Central airway obstruction (CAO) is one of the most challenging, potentially lethal complications in malignant and benign respiratory diseases. Worsening dyspnea is also a relevant cause for reduced quality of life in such patients. Here, we present our data on the application of covered, self‐expanding Y‐carina nitinol stents due to benign and malignant diseases.

Methods

We retrospectively identified 27 patients who had undergone 31 rigid bronchoscopies with implantation of covered Y‐carina nitinol stents over a period of 10 years in order to evaluate indication, clinical course, and outcome.

Results

Short‐term survival of successfully stented patients with palliative and curative treatment goal did not differ, allowing for diagnosis independent indication. With respect to overall survival, patients with endoluminal obstruction benefited most compared to patients with fistula and/or external compression. Granulation tissue formation (61.3%) and mucus plugging (80.6%) were the most frequent complications. Material defect (6.5%) and migration (3.2%) were rare complications that could be handled by revisional rigid bronchoscopy and stent exchange in some cases.

Conclusions

Implantation of self‐expanding covered Y‐carina nitinol stents via rigid bronchoscopy is a feasible and safe treatment option for benign and malignant central airway obstruction. Especially in palliative, malignant airway stenosis, stenting might facilitate additional treatment options and optimize dyspnea and eventually quality of life.

Predictors of survival and technical success of bronchoscopic interventions in malignant airway obstruction

Background

Malignant airway obstruction (MAO) leads to quality of life impairment and increased mortality. Interventional bronchoscopy allows airway patency restoring, leading to a better survival. We investigated predictors of survival and successful bronchoscopic intervention among MAO patients.

Methods

This observational prospective study enrolled 100 patients who were newly diagnosed with MAO. Survival was estimated with Kaplan-Meier method and curves compared by log-rank test. Multivariate analyses were performed using Cox proportional hazard models. Univariate and multivariate logistic regression were used for odds ratio calculation.

Results

A proportion of 73% of the patients were male with a median age was 62.5 years (range, 21–88 years). Lung cancer was the most common primary malignancy (74%). The majority had single (61%), endoluminal (62%) lesions and were classified as grade III in Myer Cotton scale (57%). The most used techniques comprised mechanical debulking (n=81) and laser therapy (n=68). Twenty-two airway stents were placed. While eleven patients were considered untreatable, technical success was achieved in 78%. Haemorrhage was the most common acute complication (16%). No deaths occurred as a result of the procedure. Median global survival was 8 months. Adjusting for age and Eastern Cooperative Oncology Group Performance Status (ECOG), extrinsic compression or mixed airway obstructions [hazard ratio (HR) =2.075; P=0.012], successful bronchoscopic intervention (HR =0.468; P=0.025) and initiation of cancer treatment (HR =0.373; P=0.006) were independent predictors of survival. The absence of distal airway patency on thoracic CT was independently associated with failure of the intervention [odds ratio (OR) =0.013; P<0.001].

Conclusions

Interventional bronchoscopy has proven to be an efficient and safe strategy to manage MAO patients. The patients who benefit the most in terms of survival are those with purely endoluminal lesions, in whom technical success was achieved and those whose cancer-specific treatment was initiated. Distal airway patency on thoracic CT predicts the technical success of bronchoscopic intervention.

Current practices in the management of central airway obstruction

PURPOSE OF REVIEW

Airway obstruction continues to cause substantial pulmonary morbidity and mortality. We present a review of classic, current, and evolving management techniques, highlighting recently published studies on the topic. Recommendations have historically been primarily based on anecdotal experience, case reports, and retrospective studies, but more solid evidence has emerged in the last decade.

RECENT FINDINGS

Novel endobronchial stents are being developed to mitigate the issues of stent migration, mucus plugging, fracture, and granulation tissue formation. Endobronchial drug delivery has become an active area of translational and clinical research, especially with regards to antineoplastic agents used for malignant airway stenosis. Even classic or updated techniques such as spray cryotherapy, injections of mitomycin-c, and balloon dilation have recently been examined in methodologically sound studies. Finally, recently published data have confirmed that patient breathlessness and quality of life improve significantly with therapeutic airway interventions. A multimodal and multidisciplinary approach to patient care is key to achieving the best outcomes.

SUMMARY

The treatment of central airway stenosis is often multimodal and should focus on patient-centric factors, taking into account risks and benefits of the procedure, operator, and center expertise, and always occur in the context of a multidisciplinary approach. Evidence-based clinical research is increasingly driving patient management.

Integrated intErventional bronchoscopy in the treatment of locally adVanced non-small lung cancER with central Malignant airway Obstructions: a multicentric REtrospective study (EVERMORE)

OBJECTIVES

Despite new therapeutic perspectives, the presence of central airways occlusion (CAO) in patients with locally advanced non-small cell lung cancer (NSCLC) is associated with poor survival. There is no clear evidence on the clinical impact of interventional bronchoscopy as a part of an integrated treatment to cure these patients.

MATERIALS AND METHODS

This retrospective cohort study was conducted in two teaching hospitals over a 10 years period (January 2010-January 2020) comparing patients with NSCLC at stage IIIB and CAO at disease onset treated with chemotherapy/radiotherapy (standard therapy-ST) with those receiving interventional bronchoscopy plus ST (integrated treatment-IT). Primary outcome was 1-year survival. The onset of respiratory events, symptoms-free interval, hospitalization, need for palliation, and overall mortality served as secondary outcomes.

RESULTS

A total of 100 patients were included, 60 in the IT and 40 in the ST group. Unadjusted Kaplan-Meier estimates showed greater effect of IT compared to ST on 1-year survival (HR = 2.1 95%CI[1.1-4.8], p = 0.003). IT showed a significantly higher survival gain over ST in those patients showing KRAS mutation (7.6 VS 0.8 months,<0.0001), a lumen occlusion >65% (6.6 VS 2.9 months,<0.001), and lacking the involvement of left bronchus (7 VS 2.3 months,<0.0001). Compared to ST, IT also showed a favorable difference in terms of new hospitalizations (p = 0.03), symptom-free interval (p = 0.02), and onset of atelectasis (p = 0.01).

CONCLUSIONS

In patients with NSCLC stage IIIB and CAO, additional interventional bronchoscopy might impact on 1-year survival. Genetic and anatomic phenotyping might allow identifying those patients who may gain life expectancy from the endoscopic intervention.