Malignant Airway Obstruction Research Articles

Update in airway stents

Malignant central airway obstruction heavily impacts patients' quality of life and its management continues to be a challenge. The current article will review the use of airway stents in this population. Airway stenting is highly effective in palliating symptoms of airway obstruction. There are several types of stents available with different advantages and disadvantages depending mainly on the material they are made from. Clinical outcomes seem to be comparable between silicone and self-expanding metal stents. Self-expanding metal stents have proven to be efficient in recanalizing 'complex' central airway obstructions. Preliminary data show that a new self-expanding 'hybrid' stent appears to be effective and safe for malignant airway obstruction. Airway stent complications vary according to the type of stent and the type of obstruction. Multidetector computed tomography seems to be a valuable adjunct to bronchoscopy in detecting and characterizing stent complications. A clear definition of airway stent-related infection is urgently needed to provide adequate diagnosis and management of this complication. Metal stent fracture is less common in patients with malignant airway obstruction as compared with benign disease, and this could be partially explained by the decreased survival and shorter exposure to stent in the former population. Airway stents are of great help in palliating symptoms of malignant central airway obstruction. Unfortunately, there have been no recent striking advances in stent technology and the ideal stent has yet to be designed.

Practice Patterns for Maintaining Airway Stents Deployed for Malignant Central Airway Obstruction

Although significant experience exists in placing airway stents, and knowledge of stent-related complications is widespread, information is lacking regarding methods of surveillance and maintaining patency of these stents. The purpose of this investigation was to determine the actual practice patterns used by interventional pulmonologists for airway stent maintenance. We prospectively surveyed members of the American Association of Bronchology and Interventional Pulmonology or attendees at their annual meeting during Chest 2008. Sixty-two respondents returned the completed surveys and were included in the analysis. Practice settings included university (50%), single specialty (27%), community academic (11%), and multispecialty (11%) settings. Annual placement of stents was ≤10 (31%); 11 to 30 (45%); and >30 (24%). Considerable variability existed in both medications used for maintenance and surveillance schedules, and less than 50% protocolized postplacement management. Although stent placement is common among experienced interventional pulmonologists, half have no protocol for surveillance or maintenance. Similarly, there is no discernable consistency or standard practice pattern to monitor for or prevent stent failure. Further study is required to determine the best practices for postdeployment surveillance and maintenance of airway stents.

Computed Tomography Measurements for Airway Stent Insertion in Malignant Airway Obstruction

Metallic airway stents for malignant airway obstruction are considered safe, yet are not without complications. This study reviews the role of computed tomography (CT) airway measurements for planning stent placement in malignant airway obstruction before the actual therapeutic procedure to avoid invasive diagnostic evaluation before the stent placement and to reduce complications. This study is a retrospective review of information from a stent order database and medical records of patients receiving stents for malignant airway obstruction at a university hospital over a 12-year period. CT scans were used to determine stent diameter by calculating mean diameters of healthy adjacent zones (proximal and distal), stent length (length of diseased airway), and location and number of potential stents. Results of CT planning before bronchoscopy were judged by complication rates. Patient population consisted of 69 patients, 61.7±14.0 years old, 40 males, in whom 92 stents were inserted. The most frequent cause of airway obstructions was tracheobronchial cancer (32). All patients had nitinol stent placement; 66 stents were covered and 26 were uncovered. Follow-up time was 1 to 1067 days (median: 35 days). Complication rate was 10.1% and mainly involved the patients with tracheal obstruction (6). Complications included stent fractures (2), migration (2), granuloma (1), and infectious tracheitis (2). One early death within 24 hours after the procedure was not related to stent placement. Five patients required follow-up therapeutic bronchoscopy to treat the complications. These results suggest that prestent planning by noninvasive method of obtaining CT scan provides optimal stent size and position, possibly avoiding a diagnostic bronchoscopy and reducing complications. Further prospective study is needed to confirm these results because of limitation of this study's design.

Therapeutic bronchoscopy for malignant airway stenoses: Choice of modality and survival

There are no data regarding the factors influencing the choice of therapeutic bronchoscopic modality in the management of malignant airway stenoses. To assess the choice of therapeutic bronchoscopy modality and analyze factors influencing survival in patients with malignant central airway obstruction. We performed 167 procedures in 130 consecutive patients, for malignant central airway obstruction, over six years. Laser was used either alone or in combination with stent insertion in 76% procedures. Laser only was used in 53% procedures for lesions below the main bronchi. Stents alone were used for extrinsic compression or stump insufficiency. Combined laser and stent insertion was most frequently used for lesions involving the trachea plus both main bronchi or only the main bronchi. The Dumon stent was preferred in lesions of the trachea and the right bronchial tree, the Ultraflex stent for lesions on the left side and stenoses below the main bronchi. Survival was better in patients with lung cancer, lesions restricted to one lung and when laser alone was used compared to esophageal cancer, metastases and tracheal involvement. The choice of different airway stents can be made based on the nature and site of the lesion. Dumon stents are suited for lesions in trachea and right main bronchus and the Ultraflex stents on the left side and stenoses beyond the main bronchi. Survival can be estimated based on the diagnosis, site of the lesion and treatment modality used.

Tracheal restenosis after removal of long-term placed Ultraflex expandable metallic stents

Restenosis of trachea after stent placement and removal in patients with malignant airway obstruction has rarely been reported. Here, we reported a 47-year-old woman with large B cell lymphoma at the mediastinum. It was obstructing the trachea and left main bronchus. Two Ultraflex expandable metallic stents were placed immediately due to acute respiratory distress. She underwent concurrent chemoradiotherapy for the lymphoma with good response. Because granulation tissue overgrew the upper margin of the trachea stent and caused frequent sputum impaction, stents were removed after 21 months. Dyspnea developed 8 months later. Bronchoscopy revealed restenosis from granulation tissue and fibrosis at the previous upper margin of the trachea stent. Segmental resection of trachea with primary anastomosis was performed and the patient recovered. Thus, tracheal restenosis may still occur in malignant obstruction patient undergoing Ultraflex stents insertion. Surgery remains a feasible treatment if underlying malignancy is in remission.

The acute remedy of malignant central airway obstruction

Objective To explore the palliative methods to patients with central airway obstruction due to advanced malignancies.

Mediastinal Migration of Self-Expanding Bronchial Stents in the Management of Malignant Bronchoesophageal Fistula

Airway stents are commonly used to palliate malignant central airway obstruction and tracheo-/bronchoesophageal fistulas. Despite their efficacy in immediately relieving airway obstruction, they can be associated with a variety of complications. We report the case of a 44-year-old woman with a malignant bronchoesophageal fistula treated initially with a self-expanding silicone mesh stent in the left main bronchus followed 2 weeks later by an esophageal stent. Shortly afterward, she presented with chest pain, worsening cough, and breathlessness. A CT scan of the chest revealed the airway stent in the contralateral mediastinum perforating the right main bronchus. We discuss her subsequent management and complications associated with self-expanding airway stents in this setting.

Silicone Y stent placement at secondary left carina for malignant central airway obstruction

The Y silicone stents are shaped with long tracheal and left main bronchial limbs and a shorter right main bronchial limb. These stents can be used for patients with fixed or dynamic central airway obstruction from benign or malignant disease. 1 More often, these stents are used for patients with extensive tumor involvement in the lower trachea and mainstem bronchi. 2 To our knowledge, their use specifically for unilateral central airway obstruction has not been previously published. In this report, we describe the indication, method, and outcome of Y stent insertion at the level of the secondary left carina separating the left upper and lower lobe bronchi, to restore airway patency ofthe left lobar bronchi in a patient with primary squamous cell lung cancer. CLINICAL SUMMARY A7 3-year-old man with hemoptysis was found to have a left infrahilar mass involving the distal left main bronchus and the entrance of the lobar bronchi (Figure 1). Rigid bronchoscopy, neodymium:yttrium-aluminum-garnet laser photocoagulation and debulking was performed under general anesthesia with assisted spontaneous ventilation using a 13-mm Efer-Dumon rigid ventilating bronchoscope (Bryan Corporation, Woburn, Mass). Tumor infiltration, cartilaginous collapse, and extrinsic compression prompted insertion of a Y silicone stent (16-mmdiameter tracheal, 12-mm-diameter bronchial limbs) within the left main bronchus. The left bronchial limb was shortened to 1.5 cm using a scalpel prior to loading the longitudinally folded stent into a large, rigid, stent introducer tube. The stent was then deployed into the entrance of the left upper lobe bronchus. While the stent was still partially folded along its long axis, rigid forceps were used to grasp the stent and pull it proximally into the distal left main bronchus, allowing unfolding of the right bronchial limb into the relatively straight left lower lobe bronchus. Forceps were then used to push the stent down onto the secondary left carinal spur. The right limb of the Y stent was thus directed into the left lower lobe bronchus while the left limb was shortened to provide access into the left upper lobe bronchus (Figure 2). There were no perioperative complications. The patient received chemotherapy and radiation therapy. Bronchoscopy 4 months later revealed patent airways and no evidence of stent-related complications. At 1-year follow-up, the patient’s airways remain patent.

A Prospective Multicenter Trial of a Self-expanding Hybrid Stent in Malignant Airway Obstruction

A Prospective Multicenter Trial of a Self-expanding Hybrid Stent in Malignant Airway Obstruction

Endobronchial Intratumoral Chemotherapy

Endobronchial Intratumoral Chemotherapy

Use of a Retrievable Metallic Stent Internally Coated with Silicone to Treat Airway Obstruction

The authors hypothesized that internally covered stents can reduce the rates of stent migration or mucous retention. The authors performed this study to report their experience with use of a retrievable metallic stent internally coated with silicone in patients with benign or malignant central airway obstructions. From 2004 to 2007, the authors performed fluoroscopically guided placement of a retrievable metallic stent internally coated with silicone in 26 consecutive patients with benign (n = 5) and malignant (n = 21) central airway obstructions. Stents were woven from a single thread of a 0.2-mm-diameter nitinol wire in a tubular configuration and internally covered with silicone membrane. Stent placement was technically and clinically successful in 93% (25/26) and 85% (22/26) of the patients, respectively. There were eight complications (31%) after stent placement, including tumor overgrowth (n = 2), stent migration (n = 1), symptomatic granulation tissue formation (n = 1), severe pain (n = 1), improper stent location (n = 1), symptomatic sputum retention (n = 1) and esophagobronchial fistula (n = 1). Because of complications, five stents were removed with a retrieval hook under fluoroscopic guidance without difficulty. The median survival period and stent patency were 150.0 days +/- 91.4 and 143.0 days +/- 26.7, respectively. The use of a retrievable metallic stent internally coated with silicone is a safe and effective method for relieving dyspnea, with adequate stent patency in patients with benign or malignant central airway obstructions. This stent design seems to be less prone to migration or mucous retention.

Tracheobronchial stenting and central airway replacement

The present paper reviews the recent literature on the management of malignant large airway obstruction using tracheobronchial stenting and airway replacement by aortic allografts. Airway stenting is a valuable adjunct to therapeutic bronchoscopy to relieve malignant airway obstruction. Over 80% of patients with obstructing lesions who were treated by airway stenting presented immediate symptom improvement in recent series. Stenting may also function as a bridge until further curative treatment can be used. Different stent models are available; their advantages and disadvantages depend on materials and constructions; clinical experience is larger with silicon-based models than with metallic stents. An alternative strategy for the management of nonresectable primary tracheal tumors aiming to replace the central airway with an allogenic aortic allograft has been proposed. Experimental studies showed that an aortic allograft produced a respiratory conduit that shared fundamental elements of the trachea and newly formed cartilage rings were observed. Airway stenting provides efficient palliation of symptoms in patients with malignant central airway obstruction. Evidence-based studies are needed to identify patients who may have the greatest benefit from stenting. Tracheal replacement with allogenic aortic allografts is a novel technique which brings hope to the management of extensive tracheal lesions.

Long-Term Follow-Up of Ultraflex Metallic Stents in Benign and Malignant Central Airway Obstruction

We report experience with Ultraflex metallic stents (Boston Scientific, Natick, MA) inserted at rigid bronchoscopy under general anesthesia for palliation of benign and malignant upper airway obstruction. Notes of all patients treated with Ultraflex stents from 1999 to 2003 were reviewed for symptomatic response, spirometric data, and any complications before discharge home. Long-term outcome was assessed by questionnaires sent to patients' general practitioners. Recruited were 66 patients (12 benign, 54 malignant airway obstructions). Before discharge home, breathlessness improved in 11 of 12 patients with benign obstruction and in 39 of 54 with malignancies. Postoperative complications in 10 patients with malignant obstructions and in 2 patients with benign obstruction were successfully controlled. It was not possible to perform preoperative pulmonary function tests in most of the patients who presented as emergencies. Mean improvement in forced expiratory volume in 1 second was 0.88 liters in 3 patients with benign obstruction and 0.28 liters in 14 patients with malignant obstruction, and mean peak expiratory flow rate improved by 109 L/min and 97 L/min, respectively. General practitioners completed questionnaires for 12 benign patients and 46 of 54 patients with malignancies. At a mean follow-up of 1017 days (range, 46 to 1120 days), 10 of the 12 patients with benign disease were alive and 7 of 46 patients with malignant airway obstruction were alive, with a median survival of 128 days (mean, 361; range, 3 to 1859 days). Most survivors had Medical Research Council grade III breathlessness or better, with few stent-related symptoms. Ultraflex stents proved safe and effective in prolonged palliation of benign and malignant airways obstruction.

Endoscopic argon plasma coagulation for the management of solid, centrally located lung cancer

Argon plasma coagulation (APC) is one of the interventional pulmonology techniques primarily aimed at the treatment of hemoptysis. It represents a form of non contact electrosurgey that uses ionized argon gas in order to produce electrical current that affects soft tissues. APC is reported to be effective in the treatment of early stage lung cancer, in the treatment of benign granulation tissue surrounding tracheal stents and in palliative treatment of malignant airway obstruction. Major indication for APC is hemostasis in severe hemoptysis, it can also be used as an alternative technique for laser resection or electrocautery, in urgent removal of tumors situated in large airways. The present article reports successful use of APC in the treatment of centrally located squamous cell lung cancer that caused complete right lung atelectasis. The use of APC led to complete reexpansion of the right lung and improvement in dyspnoea and chest discomfort of the patient. Significant improvement was observed in lung function parameters and blood gas analysis. With the use of APC solid tumor was completely removed from the right main bronchus and airway integrity was restored. From this case we can conclude that APC can be safely and successfully used for urgent debulking of malignant central airway obstruction.

Performance of a Self-Expanding Silicone Stent in Palliation of Benign Airway Conditions

The Polyflex stent (Boston Scientific; Boston, MA) is a self-expanding, thin-walled, silicone stent. Its use has been described in the management of patients with malignant airway obstruction, yet reports of its use for treatment of benign airway conditions are rare. We report a retrospective review of our experience with the Polyflex stent in the management of benign airway conditions. A total of 16 stents were deployed in 12 patients. The indications for the stent placement included the following: anastomotic stenosis following lung transplantation (LTR) [four patients]; tracheal stenosis (three patients); tracheobronchomalacia (two patients); tracheobronchopathiaosteochondroplastica (one patient); relapsing polychondritis (one patient); and bronchopleural fistula (one patient). Even though immediate palliation was established in most cases (90%), the incidence of complications was 75%. Stent migration was the most common consequence, with time to the event ranging from < 24 h to 7 months. One stent was expectorated within < 24 h. One patient coughed up a portion of the inner lining of the stent 7 months after its placement. Emergent bronchoscopy was required in four patients for mucous impaction. The complication rate was 100% in patients with LTR-related anastomotic stenosis. The use of the Polyflex stent for the treatment of benign airway conditions is associated with a high complication rate. We have abandoned its use under such conditions in our practice.

OUTCOME OF TREATED, ADVANCED, NON-SMALL CELL, LUNG CANCER WITH AND WITHOUT CENTRAL AIRWAY OBSTRUCTION

In patients with advanced non-small cell lung cancer (NSCLC) treated with chemotherapy, we compared survival in patients with treated central airway obstruction to those who did not have central airway obstruction. One hundred forty-four patients with advanced and inoperable NSCLC were included. These consisted of 52 consecutive patients treated with therapeutic bronchoscopy plus chemotherapy with or without radiotherapy (group A) and 92 consecutive patients who did not have central airway obstruction treated with chemotherapy alone (group B). Chemotherapy consisted of cisplatin or carboplatin, and one third-generation chemotherapy agent. There was no significant difference in the survival of patients with and without central airway obstruction (p = 0.395). There was no influence of the histologic subtype on survival in both groups combined and also in each group separately. Median survival in patients belonging to group A was 8.4 months and those in group B was 8.2 months; 3-, 6-, and 12-month survival rates in patients in group A were 90%, 71%, and 40%, respectively, and those in group B were 82%, 63%, and 34%. Patients having advanced NSCLC with locally treated malignant central airway obstruction in combination with chemotherapy do not have a worse survival compared to those with advanced NSCLC without central airway obstruction. Therapeutic bronchoscopy should be offered to patients with NSCLC and central airway obstruction.

Rigid Bronchoscopic Intervention in Patients with Respiratory Failure Caused by Malignant Central Airway Obstruction

Bronchoscopic intervention in patients with malignant central airway obstruction provides initial palliation and stabilization of the airway, allowing the possibility of other effective therapeutic modalities, such as surgery, radiation, or chemotherapy. In critically ill patients, however, the only studies of bronchoscopic intervention are relatively small series. To describe the advantages and limitations of rigid bronchoscopic intervention in critically ill patients, we reviewed the medical records of 36 patients (26 men; median age, 62 years; range, 29 to 76 years) who underwent emergency airway intervention for malignant central airway obstruction. Dyspnea was relieved in 34 of 36 patients (94.4%). After the airway was widened, additional definitive therapeutic modalities were used for 21 of 34 patients (61.8%). Patients who underwent additional definitive therapy after bronchoscopic intervention survived longer (median, 38.2 months; range 1.7 to 57.0 months) than those who did not (median, 6.2 months; range, 0.1 to 33.7 months; p < 0.001). These data show that rigid bronchoscopic intervention in critically ill patients with malignant central airway obstruction may be temporarily life-saving and, in some patients, may serve as a "bridge" to allow time for additional therapies for longer survival.

Rigid Bronchoscopic Intervention in Patients with Respiratory Failure Caused by Malignant Central Airway Obstruction

Rigid Bronchoscopic Intervention in Patients with Respiratory Failure Caused by Malignant Central Airway Obstruction

Therapeutic Bronchoscopy Interventions Before Surgical Resection of Lung Cancer

Therapeutic bronchoscopy is used for endobronchial staging of lung cancer and symptomatic relief of central airway obstruction or postobstructive pneumonia. The aim of this study was to assess the utility of therapeutic bronchoscopy as a complementary tool in the combined bronchoscopic and surgical management of malignant airway lesions before curative lung surgery. Seventy-four consecutive patients with nonsmall cell lung carcinoma undergoing a therapeutic bronchoscopy procedure followed by surgery with a curative intent were included. A single interventional bronchoscopic method was used in 27 patients (36%) and a combination of methods in 47 patients (64%). Median forced expiratory volume in 1 second (FEV1) before and after bronchoscopy were 1.7 L and 2.2 L, respectively, and forced vital capacity (FVC) was 2.5 L and 3.3 L, respectively. Sleeve upper lobectomy was performed in 22 patients (30%), sleeve upper bilobectomy in 16 patients (22%), lower bilobectomy in 2 patients (3%), pneumonectomy with sleeve resection in 2 patients (3%), and pneumonectomy in 28 patients (38%). The following surgeries were performed in 1 patient each: sleeve middle lobectomy, sleeve lower lobectomy, carina resection and complex reconstruction, and exploratory thoracotomy. Overall, parenchyma-sparing surgery (lobectomy or bilobectomy) could be performed in 57% patients after therapeutic bronchoscopy. There were no in-hospital deaths or deaths in the first 30 days after surgery. Therapeutic bronchoscopy can be used as a complementary tool in the combined bronchoscopic and surgical management of malignant airway obstruction before curative lung surgery. Therapeutic bronchoscopy might permit parenchyma-sparing surgery in patients with lung cancer.

Outcomes of Tracheobronchial Stents in Patients With Malignant Airway Disease

Malignant central airway obstruction is difficult to manage and is associated with poor outcome. We sought to identify the short (< 30 days) and intermediate (> 30 days) benefits and risks of tracheobronchial stents in patients with malignant airway disease. Two hundred and twenty-five tracheobronchial stents were placed in 172 patients for benign (n = 32) and malignant (n = 140) disease from January 1, 1997, to May 31, 2003. The records of the patients with malignant disease were retrospectively analyzed to determine complication rate, reintervention rate, and survival. The malignant diagnoses included nonsmall cell cancer, small cell cancer, esophageal cancer, and metastatic disease. There were 172 stents placed in 140 patients with malignant disease, with no intraoperative mortality. The mean follow-up period was 142 +/- 12 days. There were 23 complications, including tumor ingrowth (n = 9), excessive granulation tissue (n = 7), stent migration (n = 5), and restenosis (n = 2). Five of the complications occurred during the short-term period (< 30 days) with the remaining complications (n = 18) occurring after 30 days. The complications required interventions including laser debridement (n = 14), dilation (n = 4), and stent removal (n = 5). Tracheobronchial stents offer minimally invasive palliative therapy for patients with unresectable malignant central airway obstruction. The benefit of airway stents is particularly seen in the short-term period where they provide symptomatic improvement and have low complication risk. The major impediment is excessive granulation tissue and tumor ingrowth, which occur primarily after 30 days.