Bronchoscopic ablation techniques in the management of lung cancer

Epidemiology and Survival of Malignant Central Airway Obstruction in Lung Cancer Identified on Cross-Sectional Imaging

BACKGROUND

The prevalence of malignant central airway obstruction at diagnosis and its 5-year incidence are largely unknown, as are basic epidemiological data pertaining to this serious condition. To address these data limitations, we retrospectively collected data from the cohort of patients diagnosed with lung cancer at our institution in 2015 and followed cohort patients 5 years forward, until 2020.

METHODS

We reviewed index PET/CT or CT scans at the time of lung cancer diagnosis to identify the presence, subtype, and severity of malignant central airway obstruction as well as progression/development over the next 5 years.

RESULTS

The prevalence of malignant central airway obstruction affecting the airway lumen by 25% or greater was 17%, and its 5-year incidence of development was 8.2%. Notable associations from the multivariate analysis included a younger age and a stepwise increase in obstruction with increasing stage of disease. Squamous cell carcinoma and small-cell lung cancer were the 2 histologic subtypes with the strongest association with obstruction. The presence of malignant central airway obstruction either at time of diagnosis or on follow-up imaging was associated with significantly shortened survival (multivariate Cox proportional HR for MCAO=1.702, P<0.001).

CONCLUSION

This study provides the first systematic characterization of fundamental epidemiological data on malignant central airway obstructions at a tertiary cancer center in the United States. This data is important to inform research directions and funding efforts of this serious complication. It also serves as a baseline value against which to compare for future studies.

Investigation of Lung Cancer Cell Response to Cryoablation and Adjunctive Gemcitabine-Based Cryo-Chemotherapy Using the A549 Cell Line

Due to the rising annual incidence of lung cancer (LC), new treatment strategies are needed. While various options exist, many, if not all, remain suboptimal. Several studies have shown cryoablation to be a promising approach. Yet, a lack of basic information pertaining to LC response to freezing and requirement for percutaneous access has limited clinical use. In this study, we investigated the A549 lung carcinoma cell line response to freezing. The data show that a single 5 min freeze to -15 °C did not affect cell viability, whereas -20 °C and -25 °C result in a significant reduction in viability 1 day post freeze to <10%. These populations, however, were able to recover in culture. Application of a repeat (double) freeze resulted in complete cell death at -25 °C. Studies investigating the impact of adjunctive gemcitabine (75 nM) pretreatment in combination with freezing were then conducted. Exposure to gemcitabine alone resulted in minimal cell death. The combination of gemcitabine pretreatment and a -20 °C single freeze as well as combination treatment with a -15 °C repeat freeze both resulted in complete cell death. This suggests that gemcitabine pretreatment may be synergistically effective when combined with freezing. Studies into the modes of cell death associated with the increased cell death revealed the increased involvement of necroptosis in combination treatment. In summary, these results suggest that repeat freezing to -20 °C to -25 °C results in a high degree of LC destruction. Further, the data suggest that the combination of gemcitabine pretreatment and freezing resulted in a shift of the minimum lethal temperature for LC from -25 °C to -15 °C. These findings, in combination with previous reports, suggest that cryoablation alone or in combination with chemotherapy may provide an improved path for the treatment of LC.

Case report: Successful bronchoscopic interventional treatment of endobronchial leiomyomas

Endobronchial leiomyomas are rare benign neoplasms of the lungs that arise from the smooth muscle cells of the bronchi and bronchioles. While surgical resection is the mainstay of treatment for these tumors, bronchoscopic interventional therapies are also effective and can help preserve lung function in certain cases. A 40-year-old male patient presented with a persistent cough and sputum production for over 4 months. A chest computed tomography scan revealed nodular lesions in the lower lobe bronchus, later confirmed as an endobronchial leiomyoma. The patient refused surgical intervention and opted for minimally invasive bronchoscopic treatments, including electric snare resection, argon plasma coagulation, and balloon dilation, resulting in a successful outcome with no recurrence during follow-up. Clinicians should consider bronchoscopic interventions as a viable treatment option for endobronchial leiomyomas patients who are either ineligible for surgical resection or opt not to undergo surgery.

A Clinical Study on Video Bronchoscopy-guided Coblation for Benign Central Airway Stenosis

Background: Benign central airway stenosis poses a significant challenge to respiratory and thoracic surgeons due to the high recurrence rate associated with current treatment methods, causing severe breathing difficulties and potentially life-threatening complications. This article aims to investigate the therapeutic efficacy and prospects of using coblation in the management of benign central airway stenosis in adults. Moreover, the pathogenesis of benign central airway stenosis was deeply explored to provide better guidance for future clinical treatments. Materials and Methods: This retrospective study examined patients with benign central airway stenosis who were treated at The Second Hospital of Hebei Medical University from 2017 to 2020. In addition, a comparative analysis of whole-genome sequencing was conducted between the aforementioned patient group and healthy populations to investigate the underlying etiology of this stenotic condition. Results: The present study encompassed 32 patients who underwent 43 treatments in total between 2017 and 2020. All patients exhibited alleviation of airway stenosis and an improvement in clinical symptoms following surgery, without any significant surgical or postoperative complications. Whole-genome analysis revealed significant changes in gene expression in the airway mucosa of patients with benign airway stenosis in comparison to healthy populations. A total of 91 differentially expressed genes were identified, among which 44 upregulated genes displayed characteristics of promoting inflammatory responses. Conclusion: Coblation demonstrates promise as an efficacious treatment modality for adults suffering from benign central airway stenosis, and its widespread application in clinical settings is anticipated. The direct pathogenesis of benign central airway stenosis involves airway lumen narrowing and obstruction resulting from excessive inflammation and proliferative granulation.

Clinical Practice of Photodynamic Therapy for Non-Small Cell Lung Cancer in Different Scenarios: Who Is the Better Candidate?

BACKGROUND

Photodynamic therapy (PDT) is a relatively safe and highly selectivity antitumor treatment, which might be increasingly used as a supplement to conventional therapies. A clinical overview and detailed comparison of how to select patients and lesions for PDT in different scenarios are urgently needed to provide a basis for clinical treatment.

SUMMARY

This review demonstrates the highlights and obstacles of applying PDT for lung cancer and underlines points worth considering when planning to initiate PDT. The aim was to make out the appropriate selection and help PDT develop efficacy and precision through a better understanding of its clinical use.

KEY MESSAGES

Increasing evidence supports the feasibility and safety of PDT in the treatment of non-small cell lung cancer. It is important to recognize the factors that influence the efficacy of PDT to develop individualized management strategies and implement well-designed procedures. These important issues should be worth considering in the present and further research.

Impact of Interventional Bronchoscopy on Long-Term Survival in Patients with Primary Tracheal Adenoid Cystic Carcinoma: A Single-Center Experience

Introduction

Primary tracheal adenoid cystic carcinoma (TACC) is a rare low-grade lung cancer of bronchial gland origin. Surgery is the first choice of treatment; however, in cases of recurrence or inoperability, a combination of radiation and chemotherapy is administered as a multimodality treatment. Interventional bronchoscopy is also used as a multidisciplinary treatment; however, its impact on long-term prognosis has not been thoroughly investigated.

Case Presentation

Eight patients diagnosed with TACC and treated at Shinshu University Hospital between December 2000 and August 2023 were analyzed retrospectively. We investigated the duration of intervention and overall survival (OS) in 3 patients with recurrence who underwent interventional bronchoscopy in combination with chemotherapy and evaluated whether interventional bronchoscopy prolonged the survival. The initial treatment for the 3 patients was surgery in 1 patient and chemoradiotherapy in 2. In all patients, raised lesions were observed in the trachea at the time of recurrence. The duration of interventional bronchoscopy, the time from recurrence of the first-line treatment to death, and OS, which was defined time from induction of the first-line treatment to death, were 69.3/70.7/112.5 months, 179.2/196.1/220.4 months, and 15.4/66.3/104.4 months, respectively.

Conclusion

Long-term survival benefits may be obtained with concomitant interventional bronchoscopy in combination with chemotherapy in patients with locally recurrent TACC.

Palliative management of a malignant tracheoesophageal fistula using repeat endobronchial laser debridement and esophageal stenting

A 71-year-old female presented with progressive dysphagia and unexplained weight loss. Computed tomography and esophagogastroduodenoscopy (EGD) revealed invasive esophageal squamous cell carcinoma, which was initially treated with local radiation and esophageal stenting. Over the next year, the patient experienced multiple symptoms and hospital admissions consistent with a malignant tracheoesophageal fistula, despite negative findings on imaging, bronchoscopy, and EGD. Prophylactic antibiotics were initiated based on symptomatology to prevent septic episodes. Stent erosion into the membranous trachea was eventually observed. Neodymium-yttrium-aluminum-garnet laser bronchoscopy was used periodically to debulk the invading tumor around the stent. A percutaneous endoscopic gastrostomy tube was also inserted to facilitate enteral nutrition and avoid aspiration pneumonia. The patient reported significant improvements in respiratory symptoms following each laser debridement and has progressed well beyond the life expectancy associated with malignant tracheoesophageal fistula.

An overview on the principles of management of haemoptysis

Haemoptysis is a frequently encountered presentation in thoracic surgery practice. Most of the patients present with chronic haemoptysis while 5% of them will present with life-threatening acute haemoptysis. Emergency surgery used to be the first-line management in acute life-threatening haemoptysis which resulted in significant morbidity and mortality. With advancements in interventional procedures, most of these acute presentations are now being managed conservatively by interventionists. In a country like India with a high incidence of tuberculosis and other infectious diseases of the lungs, haemoptysis is even more common. While interventional procedures help to tide over the crisis and earn valuable time to stabilise a haemorrhaging patient, surgical resection is the definitive management most of the time. This review will endeavour to establish the definition, aetiology, emergency, and definitive management of a patient who presents with haemoptysis.

Thermoablative Techniques to Treat Excessive Central Airway Collapse

Excessive central airway collapse (ECAC) is a condition characterized by the excessive narrowing of the trachea and mainstem bronchi during expiration, which can be caused by Tracheobronchomalacia (TBM) or Excessive Dynamic Airway Collapse (EDAC). The initial standard of care for central airway collapse is to address any underlying conditions such as asthma, COPD, and gastro-esophageal reflux. In severe cases, when medical treatment fails, a stent-trial is offered to determine if surgical correction is a viable option, and tracheobronchoplasty is suggested as a definitive treatment approach. Thermoablative bronchoscopic treatments, such as Argon plasma coagulation (APC) and laser techniques (potassium-titanyl-phosphate [KTP], holmium and yttrium aluminum pevroskyte [YAP]) are a promising alternative to traditional surgery. However, further research is needed to assess their safety and effectiveness in humans before being widely used.

Therapeutic bronchoscopy followed by sequential radiochemotherapy in the management of life-threatening tracheal adenoid cystic carcinoma: a case report

Background

Adenoid cystic carcinoma of the lung is a distinctive salivary-gland-type malignant epithelial neoplasm that rarely presents as a primary tumor of the respiratory tract. Complete surgical resection remains the treatment of choice for adenoid cystic carcinoma. We present a case of large ACC tumors that caused severe central airway obstruction and were effectively treated with therapeutic bronchoscopy followed by radiotherapy and chemotherapy.

Case presentation

A 31-year-old Malay Indonesian female patient who was a nonsmoker and had no family history of cancer was admitted to the emergency ward because of worsening breathlessness accompanied by stridor since 1 week prior. Chest computed tomography revealed segmental atelectasis of the left lung; a mass on the left main bronchus, with infiltrates in segments 1, 2, and 3 of the left lung; and consolidation in the left inferior lobe, with narrowing of the main left bronchus. Lobulated masses obstructing almost the entire distal trachea up to the carina and the entire left main bronchus were found on bronchoscopy. Owing to the large tumors causing severe central airway obstruction, the medical team decided to perform central airway mass removal through rigid bronchoscopy. A neodymium-doped yttrium-aluminum-garnet laser was used first to facilitate mass shrinkage. After the laser treatment, mechanical mass removal using a rigid scope was performed. The tracheal and carinal lumens were opened to > 50% of their diameter, with the left main bronchus lumen opened only slightly. After the treatment, the patient was stable, and no stridor was found. Adjuvant intensity-modulated radiotherapy and chemotherapy were performed after the therapeutic bronchoscopy. At the end of the entire treatment, reevaluation by thoracic computed tomography scan and bronchoscopy revealed no remaining mass.

Conclusions

In cases of nonresectable large adenoid cystic carcinoma tumors with life-threatening central airway obstruction, therapeutic bronchoscopy followed by sequential radiochemotherapy might achieve a complete response outcome.

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.

Medical Thoracoscopic Thermal Ablation Therapy for Metastatic Pleural Tumors with Malignant Effusion: An Exploratory Retrospective Study

Purpose

Malignant pleural effusion (MPE) is an intractable condition. The current mainstream therapies for MPE, ie, indwelling pleural catheter and pleurodesis, have some drawbacks. In this retrospective study, we explored the efficacy and safety of medical thoracoscopic thermal ablation (argon plasma coagulation, APC) therapy for metastatic pleural tumors with MPE.

Patients and Methods

A total of 176 patients were enrolled and divided into catheter pleural drainage (CPD) group (n = 77), non-ablation group (n = 46), and thermal ablation group (n = 53). Propensity score matching (PSM) was used for between-group comparisons to minimize bias. The primary endpoints were pleural effusion objective response rate (ORR) and time to progression (TTP); secondary endpoints included overall survival (OS), chest-tube duration, and safety.

Results

Thermal ablation group and non-ablation group showed significantly higher ORR and shorter chest-tube duration versus the CPD group (ORR: thermal ablation, 88.2% vs 66.7%, P = 0.004; non-ablation, 88.4% vs 64.4%, P = 0.042; chest-tube duration: thermal ablation, 4.90 vs 7.24 days, P < 0.001; non-ablation, 5.73 vs 7.33 days, P = 0.010). Thermal ablation group exhibited longer TTP than the CPD group (median, 13.7 vs 7.3 months, P = 0.001) and the non-ablation group (median, 13.6 vs 10.3 months, P = 0.037). OS in the thermal ablation group was numerically longer than that in the CPD group with marginally significant difference (P = 0.055). There was no significant difference in the frequency of adverse events or changes in vital signs between thermal ablation and non-ablation groups.

Conclusion

Medical thoracoscopic thermal ablation (APC technique) therapy was effective and safe in the treatment of metastatic pleural tumors with MPE for improving ORR and TTP.

Imaging of therapeutic airway interventions in thoracic oncology

Tracheobronchial obstruction, haemoptysis, and airway fistulas caused by airway involvement by primary or metastatic malignancies may result in dyspnoea, wheezing, stridor, hypoxaemia, and obstructive atelectasis or pneumonia, and can lead to life-threatening respiratory failure if untreated. Complex minimally invasive endobronchial interventions are being used increasingly to treat cancer patients with tracheobronchial conditions with curative or, most often, palliative intent, to improve symptoms and quality of life. The selection of the appropriate treatment strategy depends on multiple factors, including tumour characteristics, whether the lesion is predominately endobronchial, shows extrinsic compression, or a combination of both, the patient's clinical status, the urgency of the clinical scenario, physician expertise, and availability of tools. Pre-procedure multidetector computed tomography (MDCT) imaging can aid in the most appropriate selection of bronchoscopic treatment. Follow-up imaging is invaluable for the early recognition and management of any potential complication. This article reviews the most commonly used endobronchial procedures in the oncological setting and illustrates the role of MDCT in planning, assisting, and follow-up of endobronchial therapeutic procedures.

Brachytherapy for lung cancer

Brachytherapy (BT) is a minimally invasive anticancer radiotherapeutic modality where the tumor is directly irradiated via a radioactive source that is precisely implanted in or adjacent to the tumor. BT for lung cancer may be conducted in the form of endobronchial BT and radioactive seed implantation (RSI-BT), mainly for nonsmall cell lung cancer (NSCLC). For patients with early-stage lung cancer who are not suitable for surgery or external beam radiotherapy (EBRT), BT may be used as an alternative treatment, and curative results could be achieved in certain patients with cancer confined to the trachea lumen. For patients with locally advanced/metastatic lung cancer, BT could be selectively applied alone or as a boost to EBRT, which could improve the local tumor control and patient's survival. In addition, BT is also useful as a salvage treatment in select patients with locally recurrent/residual lung cancer that failed other treatments (e.g., surgery, chemotherapy, and EBRT). However, clinical outcomes are mainly obtained from retrospective studies. Prospective studies are limited and needed. In recent years, the introduction of modern image guidance, novel radioactive seeds, BT treatment planning systems (BT-TPS), after-loading technique, and three-dimensional printing template (3D-PT) assistance, among others, have potentially improved the clinical outcomes of BT. However, a comprehensive review of BT with newly published literature was lacking. This review is to discuss BT for NSCLC based on recent literature published in PubMed.

Bronchoscopic treatment of inoperable nonsmall cell lung cancer

Patients with unresectable lung cancer range from those with early-stage or pre-invasive disease with comorbidities that preclude surgery to those with advanced stage disease in whom surgery is contraindicated. In such cases, a multidisciplinary approach to treatment is warranted, and may involve medical specialties including medical oncology, radiation oncology and interventional pulmonology. In this article we review bronchoscopic approaches to surgically unresectable lung cancer, including photodynamic therapy, brachytherapy, endoscopic ablation techniques and airway stenting. Current and past literature is reviewed to provide an overview of the topic, including a highlight of potential emerging approaches.

Metformin and oxyphotodynamic therapy as a novel treatment approach for triple-negative breast cancer

Background

Treatment for triple-negative breast cancer (TNBC) remains a significant challenge due to a lack of targeted therapies. While photodynamic therapy (PDT) has been utilized as a treatment approach for several types of cancer, oxyphotodynamic therapy (OPDT) is a novel method that improves treatment efficacy by increasing local oxygen concentration. Metformin (MET) has been demonstrated utility as an anti-tumor agent by acting through the adenosine monophosphate-activated protein kinase (AMPK) pathway. We hypothesized that MET in combination with heme, a byproduct of 5-aminolevulinic acid (ALA), may increase cytotoxicity for cancer treatment. This study aimed to investigate the synergistic effect of MET and ALA with PDT or OPDT on TNBC tumorigenic cells.

Methods

The treatment efficacy and phototoxicity of PDT or OPDT were determined using a cell viability assay. PDT/OPDT experiments were carried out in nine groups based on different combinations and concentrations of ALA and/or MET. To calculate the synergistic effect by compuSyn soft for different groups, cells were incubated with ALA and/or MET at the following concentrations (0, 0.25, 0.5,1, 2, 4, 8, 16, 24, and 32 mM). The fluorescence of ALA-induced protoporphyrin IX (PpIX) and MitoTracker Green were observed under a confocal microscope.

Results

The optimized therapeutic concentration ratio of ALA and MET was determined to be 1:1. The inhibition of cancer growth (IC₅₀) for each group was 14.03, 10.62, 7.71, 18.27, 22.09, 23.96, 4.57, 10.20, and 8.18 mM, respectively. The combination index (CI) values (fa =0.5) of the last three combination groups (groups 7, 8, and 9) were 0.44, 1.70, and 1.47, respectively. PpIX fluorescence intensity of group 9 (ALA-MET-OPDT group) remained the highest among all groups, indicating an enhanced therapeutic effect.

Conclusions

This study introduces OPDT as a novel anti-tumor therapy for TNBC. Furthermore, the combined use of ALA and MET had a synergistic anti-tumor effect in TNBC cells when combined with OPDT.

Bronchoscopic treatments for early-stage peripheral lung cancer: Are we ready for prime time?

Lung cancer is the leading cause of cancer-related death worldwide and surgical lobectomy remains the preferred therapy for patients with early-stage NSCLC. Medical comorbidities and advanced age preclude resection in many patients and minimally invasive ablative therapies are needed for treatment. Stereotactic ablative radiation is established as an effective modality in this patient group, although may be contraindicated in some patients with prior radiation exposure, comorbidities or centrally positioned tumours. Percutaneous ablative methods are available, although are frequently associated with significant complications. Numerous endoscopic ablative techniques are under evaluation. With a more favourable safety profile and the ability to provide diagnosis and staging information potentially within a single procedure, there is a strong rationale for development of bronchoscopic ablative modalities. In the following article, the authors aim to explore the role bronchoscopic ablation may play in treatment of peripheral lung tumours, and to describe a pathway to establishing these modalities as part of routine care. The current status of several bronchoscopic ablative options is discussed in detail.