The efficacy of external beam radiotherapy for airway obstruction in lung cancer patients

Short-course Radiotherapy for Airway Stenting in Malignant Airway Obstruction: A Case Report and Literature Review

Background

Malignant airway obstruction (MAO) secondary to tumor growth occurs in nearly a third of patients with lung cancer and portends a very poor prognosis if untreated. Treatment options include bronchoscopic intervention with tumor debulking, stent placement, endobronchial brachytherapy, or palliative radiotherapy.

Case Report

This is a report of a 74-year-old woman with a medical history of metastatic lung adenocarcinoma, hospitalized for dyspnea, hemoptysis, and chest pain with a radiographic finding of MAO on chest X-ray and computed tomography. Patient underwent radiation with a total dose of 13 Gy in two once-weekly fractions of 6.5 Gy per fraction. Three days after the end of radiation treatment, chest X-ray showed a completely right lung re-expansion without atelectasis. Two weeks after radiotherapy treatment, the patient was discharged from hospital without pulmonary symptoms.

Conclusion

A different fractionation with a lower equivalent dose in 2 Gy fraction compared to literature data showed efficacy in resolving MAO with excellent local control in the first three months of follow-up.

Mid-treatment adaptive planning during thoracic radiation using 68 Ventilation-Perfusion Positron emission tomography

Four-Dimensional Gallium 68 Ventilation-Perfusion Positron Emission Tomography (⁶⁸Ga-4D-V/Q PET/CT) allows for dynamic imaging of lung function. To date there has been no assessment of the feasibility of adapting radiation therapy plans to changes in lung function imaged at mid-treatment function using ⁶⁸Ga-4D-V/Q PET/CT. This study assessed the potential reductions of dose to the functional lung when radiation therapy plans were adapted to avoid functional lung at the mid-treatment timepoint using volumetric arc radiotherapy (VMAT).

Methods

A prospective clinical trial (U1111-1138-4421) was performed in patients undergoing conventionally fractionated radiation therapy for non-small cell lung cancer (NSCLC). A ⁶⁸Ga-4D-V/Q PET/CT was acquired at baseline and in the 4th week of treatment. Functional lung target volumes using the ventilated and perfused lung were created. Baseline functional volumes were compared to the week 4 V/Q functional volumes to describe the change in function over time. For each patient, 3 VMAT plans were created and optimised to spare ventilated, perfused or anatomical lung. All key dosimetry metrics were then compared including dose to target volumes, dose to organs at risk and dose to the anatomical and functional sub-units of lung.

Results

25 patients had both baseline and 4 week mid treatment ⁶⁸Ga-4D-V/Q PET/CT imaging. This resulted in a total of 75 adapted VMAT plans. The HPLung volume decreased in 16/25 patients with a mean of the change in volume (cc) -28 ± 515 cc [±SD, range -996 cc to 1496 cc]. The HVLung volume increased in 13/25 patients with mean of the change in volume (cc) + 112 ± 590 cc. [±SD, range -1424 cc to 950 cc]. The functional lung sparing technique was found to be feasible with no significant differences in dose to anatomically defined organs at risk. Most patients did derive a benefit with a reduction in functional volume receiving 20 Gy (fV20) and/or functional mean lung dose (fMLD) in either perfusion and/or ventilation. Patients with the most reduction in fV20 and fMLD were those with stage III NSCLC.

Conclusion

Functional lung volumes change during treatment. Some patients benefit from using ⁶⁸Ga-4D-V/Q PET/CT in the 4th week of radiation therapy to adapt radiation plans. In these patients, the role of mid-treatment adaptation requires further prospective investigation.

A Retrospective Study of Patients Undergoing Palliative Radiotherapy for Airway Obstruction due to Lung Cancer

BACKGROUND/AIM

In advanced stage lung cancer, bulky tumors can cause serious symptoms such as malignant airway obstruction (MAO). Prompt response to airway obstruction might be essential to improve quality of life and prolong life expectancy. Palliative external beam radiotherapy (EBRT) is a less invasive and highly safe treatment method that can alleviate symptoms and at the same time treat lung cancer. However, there are few reports on the results of palliative radiotherapy performed for improving airway obstruction and obstructive pneumonia. Therefore, this study retrospectively examined the effectiveness of palliative radiotherapy.

PATIENTS AND METHODS

We reviewed 38 lung cancer patients with MAO who underwent EBRT. Patients were treated with a median dose of 37.5 Gy (range=30-40 Gy) in 10-20 fractions. Whether a patient was a responder or non-responder was assessed by whether the bronchus that was obstructed before EBRT reopened or improvement of obstructive pneumonia was observed on follow-up chest X-ray or computed tomography after EBRT.

RESULTS

The median survival time was 135 days (range=31-469 days) for the responders to EBRT and 45 days (range=23-355 days) for non-responders; this difference was statistically significant (p=0.03). One-year overall survival rate was 18.5% and 0% for the responders to EBRT and non-responders, respectively.

CONCLUSION

Palliative EBRT might be an important option for non-curative lung cancer patients with MAO.

First-In-Human Computer-Optimized Endobronchial Ultrasound-Guided Interstitial Photodynamic Therapy for Patients With Extrabronchial or Endobronchial Obstructing Malignancies

Objective

Patients with inoperable extrabronchial or endobronchial tumors who are not candidates for curative radiotherapy have dire prognoses with no effective long-term treatment options. To reveal that our computer-optimized interstitial photodynamic therapy (I-PDT) is safe and potentially effective in the treatment of patients with inoperable extra or endobronchial malignancies inducing central airway obstructions.

Methods

High-spatial resolution computer simulations were used to personalize the light dose rate and dose for each tumor. Endobronchial ultrasound with a transbronchial needle was used to place the optical fibers within the tumor according to an individualized plan. The primary and secondary end points were safety and overall survival, respectively. An exploratory end point evaluated changes in immune markers.

Results

Eight patients received I-PDT with planning, and five of these received additional external beam PDT. Two additional patients received external beam PDT. The treatment was declared safe. Three of 10 patients are alive at 26.3, 12, and 8.3 months, respectively, after I-PDT. The treatments were able to deliver a prescribed light dose rate and dose to 87% to 100% and 18% to 92% of the tumor volumes, respectively. A marked increase in the proportion of monocytic myeloid-derived suppressor cells expressing programmed death-ligand 1 was measured in four of seven patients.

Conclusions

Image-guided light dosimetry for I-PDT with linear endobronchial ultrasound transbronchial needle is safe and potentially beneficial in increasing overall survival of patients. I-PDT has a positive effect on the immune response including an increase in the proportion of programmed death-ligand 1-expressing monocytic myeloid-derived suppressor cells.

Combination of Palliative Thoracic Radiotherapy With Bevacizumab for Stage IV Nonsquamous NSCLC: Is There Any Impact of Time Interval on Survival?

Background:

The time interval between palliative thoracic radiotherapy and bevacizumab treatment strongly influences the frequency of adverse events (AEs) when both are concurrently applied to patients with advanced lung cancer. Herein, we aimed to elucidate the optimal time interval between the treatments in these patients.

Methods:

The medical records of patients with stage IV nonsquamous non–small-cell lung cancer (NSCLC) without epidermal growth factor receptor and anaplastic lymphoma kinase alteration who underwent palliative thoracic radiotherapy and bevacizumab treatment from January 2008 to January 2020 were collected and analyzed. Patients were divided into 2 groups based on the time interval between treatments: <3 weeks (⩽3W group) and >3 weeks (>3W group). The progression-free survival (PFS) and overall survival (OS) for the time intervals were evaluated using the Kaplan-Meier method and Cox proportional hazard models. Adverse events were assessed by the fifth version of the Common Terminology Criteria for Adverse Events.

Results:

In total, 72 patients with stage IV NSCLC (⩽3W group, 37 patients; >3W group, 35 patients) who concurrently or sequentially received palliative thoracic radiotherapy and bevacizumab treatment were included in this study. In the >3W and ⩽3W groups, the median PFS (8 vs 6 months, respectively) and OS (15 vs 12 months, respectively) differed significantly. Multivariate analyses findings revealed significantly shorter OS in the latter group. In addition, the frequency of most AEs was marginally higher in the latter group (P > .05).

Conclusions:

The time interval between palliative thoracic radiotherapy and bevacizumab treatment that offers optimal safety is >3 weeks.

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.

Efficacy and Survival after Palliative Radiotherapy for Malignant Pulmonary Obstruction

Introduction: The purpose of this study was to determine the efficacy of palliative radiotherapy (PRT) for patients with pulmonary obstruction from advanced malignancy and identify factors associated with lung re-expansion and survival. Materials and Methods: We reviewed all patients treated with PRT for malignant pulmonary obstruction (n = 108) at our institution between 2010 and 2018. Radiographic evidence of lung re-expansion was determined through review of follow-up CT or chest X-ray. Cumulative incidence of re-expansion and overall survival (OS) were estimated using competing risk methodology. Clinical characteristics were evaluated for association with re-expansion, OS, and early mortality. Treatment time to remaining life ratio (TT:RL) was evaluated as a novel metric for palliative treatment. Results: Eighty-one percent of patients had collapse of an entire lung lobe, 46% had Eastern Cooperative Oncology Group (ECOG) performance status 3-4, and 64% were inpatient at consultation. Eighty-four patients had follow-up imaging available, and 25 (23%) of all patients had lung re-expansion at median time of 35 days. Rates of death without re-expansion were 38% and 65% at 30 and 90 days, respectively. Median OS was 56 days. Death within 30 days of PRT occurred in 38%. Inpatients and larger tumors trended toward lower rates of re-expansion. Notable factors associated with OS were re-expansion, nonlung histology, tumor size, and performance status. Median TT:RL was 0.11 and significantly higher for subgroups: ECOG 3-4 (0.19), inpatients (0.16), patients with larger tumors (0.14), those unfit for systemic therapy (0.17), and with 10-fraction PRT (0.14). Conclusion: One-fourth of patients experienced re-expansion after PRT for malignant pulmonary obstruction. Survival is poor and a significant proportion of remaining life may be spent on treatment. Careful consideration of these clinical factors is recommended when considering PRT fractionation.

Electrospray Mediated Localized and Targeted Chemotherapy in a Mouse Model of Lung Cancer

Background: An advanced stage, centrally localized invasive tumor is a major cause of sudden death in lung cancer patients. Currently, chemotherapy, radiotherapy, laser ablation, or surgical resection if possible are the available state-of-the-art treatments but none of these guarantee remedy or long-term relief and are often associated with fatal complications. Allowing localized chemotherapy, by direct and confined drug delivery only at the tumor site, could be a promising option for preoperative down staging or palliative therapy. Here we report the localized and targeted application of intra tumor delivery of chemotherapeutics using a novel device based on the principle of electrospray.

Methods: C57BL/6J mice were injected with Lewis lung carcinoma cells subcutaneously. After 15 days, the animals were anesthetized and the tumors were exposed by skin incision. Tumors were electrosprayed with 100 µg cisplatin on days 0 and 2, and tumor volumes were measured daily. Animals were sacrificed on day 7 after the first electrospray and tumors were analyzed by immunohistochemistry.

Results: In this proof-of-concept study, we report that the tumor volume was reduced by 81.2% (22.46 ± 12.14 mm³) after two electrospray mediated Cisplatin deliveries, while the control tumor growth, at the same time point, increased by 200% (514.30 ± 104.50 mm³). Moreover, tunnel and Caspase-3 positive cells were increased after Cisplatin electrospray compared to other experimental groups of animals.

Conclusion: Targeted drug delivery by electrospray is efficient in the subcutaneous mouse model of lung cancer and offers a promising opportunity for further development toward its clinical application.

A narrative review of evolving roles of radiotherapy in advanced non-small cell lung cancer: from palliative care to active player

Radiotherapy, along with other loco-regional interventions, is conventionally utilized as a palliative approach to alleviate symptoms and mitigate oncological emergencies in advanced non-small cell lung cancer (NSCLC). Thanks to the ongoing improvement of medical treatments in the last decade, such as targeted therapy and immunotherapy, the survival of patients with advanced NSCLC has been considerably prolonged, making it feasible and clinically beneficial for radiotherapy to play a more active role in highly selected subpopulations. In this review, we will focus on the evolving roles of radiotherapy in advanced NSCLC. First of all, among patients who are initially unable to tolerate aggressive treatment due to severe symptoms caused by metastases and/or tumor emergencies, timely radiotherapy could significantly improve their performance status (PS) and general condition, thus giving them a chance for intensive treatment and prolonged survival. The efficacy, potential candidates, and optimal dose-fractionation regimens of radiotherapy in this clinical scenario will be discussed. Additionally, radiotherapy can play a curative role as a concurrent therapy, consolidation therapy, and salvage therapy for patients with oligo-metastatic, oligo-residual, and oligo-progressive disease, respectively. Accumulating evidence from recent clinical trials, basic research, and translational investigations regarding the potentially curative roles of radiotherapy in NSCLC patients with oligo-metastatic disease will be summarized. Moreover, with the advent of various small molecular tyrosine kinase inhibitors (TKIs), the treatment efficacy and overall survival of oncogene-addicted NSCLC with brain metastases have been significantly improved, and the clinical value and optimal timing of cranial radiotherapy have become topics of much debate. Finally, synergistic antitumor interactions between radiotherapy and immunotherapy have been repeatedly demonstrated. Thus, the immune sensitizing role of radiotherapy in advanced NSCLC is also highlighted in this review.

Role of radiotherapy in the management of malignant airway obstruction

Background

A significant proportion of lung cancer patients suffer from malignant airway obstruction (MAO). Palliative external beam radiotherapy (EBRT) is often used to control the symptoms caused by MAO. In this study, we report the effect of palliative EBRT on lung cancer with MAO and analyze the factors that influence it.

Methods

This study included 75 patients with MAO in lung cancer who underwent palliative EBRT, between 2009 and 2018 and were analyzed retrospectively. Change of dyspnea, tumor response, and overall survival (OS) were recorded. Univariate and multivariate analyses were performed to determine the prognostic factors for treatment outcomes.

Results

The median follow‐up duration was 2.5 months, and median OS was 2.3 months. Out of 75 patients, dyspnea was improved in 46 patients (61.3%), and tumor was partially decreased in 39 patients (52%). Symptoms improved in all tumor responding patients. The symptom improvement was significantly affected by radiation dose and time to EBRT. The tumor response was significantly affected by pathology, radiation dose, and time to EBRT.

Conclusions

Palliative EBRT is an effective and safe treatment option for patients with MAO in lung cancer. In particular, high‐dose irradiation and prompt treatment can improve treatment results.

Key points

Significant findings of the study

In MAO patients, tumor response is an important factor for resolving dyspnea and improving survival rate. In order to increase the tumor response, high‐dose irradiation and prompt treatment after symptoms occur are necessary.

What this study adds

Our study reported the effects of EBRT and prognostic factors in MAO patients. We emphasize that palliative EBRT is a relatively safe and effective treatment in MAO patients, which is a complement to previous studies.

Prospective Multicentered Safety and Feasibility Pilot for Endobronchial Intratumoral Chemotherapy

BACKGROUND

Malignant airway obstruction (MAO) occurs in 30% of patients with advanced-stage lung cancer, leading to debilitating dyspnea, cough, and hemoptysis. Other than recanalization of the airways, these patients lack long-lasting palliative therapy. The goal of this study was to determine the safety and feasibility of local injection of paclitaxel into the airway wall with a novel microinjection catheter.

METHODS

In this multicentered prospective trial, 23 patients with non-small cell lung cancer and MAO were enrolled from July 2014 through June 2016 to undergo rigid bronchoscopy with recanalization, followed by injection of 1.5 mg of paclitaxel with a novel injection catheter. Primary end points consisted of safety (adverse events, severe adverse events, and unanticipated adverse device effects) as well as feasibility (number of injections, injection success). Secondary end points consisted of airway patency improvement, quality of life metrics, and need for further interventions and/or stenting.

RESULTS

Nineteen patients underwent rigid bronchoscopy with successful recanalization and paclitaxel injection. There were no adverse events, severe adverse events, or unanticipated adverse device effects. There was an average of 3.4 injections given for a total dose of 1.5 mg of paclitaxel in all patients. There was significantly less stenosis postprocedure vs preprocedure (25%-50% vs 75%-90%; P < .001), which was unchanged at 6 weeks (25%-50%). None of the participants required further interventions or airway stenting.

CONCLUSIONS

The injection of paclitaxel after recanalization of MAO in patients with non-small cell lung cancer is safe and feasible, using a novel airway injection device.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT02066103; URL: www.clinicaltrials.gov.

Postobstructive pneumonia in lung cancer

Postobstructive pneumonia can complicate lung cancer, particularly in more advanced stages of the disease, producing significant clinical decline and a poorer prognosis. It can lead to complications such as empyema, lung abscess and fistula formation. Postobstructive pneumonia can also be the first manifestation of an underlying malignancy. There are multiple challenges in the management of these patients. Recognition and treatment of this entity can be complex and includes the use of imaging, administration of broad-spectrum antibiotics to cover the wide variety of microorganisms involved and the use of different interventional modalities to relieve the obstruction. Existing literature on postobstructive pneumonia is scarce. In this article, we review the pathophysiology, different diagnostic methods and the therapeutic options to treat this condition. The utility and efficacy of the various modalities that are currently available in clinical practice to the interventional pulmonologist are described in some detail.

Endobronchial brachytherapy in the management of lung malignancies: 20 years of experience in an Australian center

OBJECTIVES

Management of end-stage lung cancers focuses on symptom control, requiring multimodality management. Endobronchial brachytherapy (EBB) is an evidence-based approach allowing safe delivery of clinically meaningful radiation doses. We provide a summary of treatment characteristics and clinical outcomes of EBB in a single center.

METHODS AND MATERIALS

Our retrospective study examined all EBB procedures performed at St George Hospital, NSW, Australia, between 1997 and 2016. Patients received single-fraction brachytherapy treatment under procedural sedation, using either the pulsed-dose-rate or high dose-rate modality. Symptomatic response was noted at the 4- to 6-week followup consultation.

RESULTS

Ninety-two EBB procedures were identified in 83 patients, with 75 patients treated with pulsed-dose-rate and 17 with high-dose-rate. Clinical and/or radiological airway obstruction in a prior high-dose irradiated volume was the most common indication for treatment (85%). Sixty (72%) patients had a partial or complete response of symptoms. Patients with hemoptysis were more likely to respond than those with airway obstruction (92% vs. 70%; p = 0.036). There was no difference in clinical response between pulsed-dose-rate and high-dose-rate patients (p = 0.24). Median overall survival was 8 months, with a statistically significant difference in those with clinical response (4 vs. 9 months; p = 0.0101). No Grade >2 toxicities were recorded.

CONCLUSIONS

We present the largest Australian series of EBB to date. We continue to demonstrate that despite a variety of symptomatic presentations and histologies, EBB is an effective approach to the palliation of malignant lung lesions. Given its low risk of toxicity, EBB is recommended as an option in the palliative treatment of endobronchial malignancies.

Functional airway obstruction observed with hyperpolarized 129 Xenon-MRI

Hyperpolarized ¹²⁹ Xenon-MRI (HP ¹²⁹ Xe MRI) is an emerging imaging modality that allows assessment of both ventilation and gas transfer. Most research to date has focused on non-malignant pulmonary diseases. However, the capability of evaluating the two primary physiological processes of the lung (ventilation and gas transfer) makes HP ¹²⁹ Xe MRI a promising imaging modality in the management of patients with lung cancer.

Palliative external beam radiotherapy for the treatment of tumor bleeding in inoperable advanced gastric cancer

Background

To assess the outcomes and prognostic factors associated with palliative external beam radiotherapy (EBRT), administered to patients with advanced gastric cancer.

Methods

Forty-two patients with bleeding gastric tumors that received EBRT for palliation were analyzed. The response to EBRT was assessed by the palliation of tumor bleeding. Patients were classified as either responders, or non-responders to EBRT. The prognostic utility of clinical and dosimetric variables was examined in a multivariate logistic regression model. The optimal dose cutoff to classify the two groups was determined with receiver operating characteristic analysis.

Results

The palliation of gastric tumor bleeding after EBRT was achieved in 29 patients (69.0%). The time to resolve tumor bleeding ranged from 1 to 84 days (median, 15 days). The median duration of palliation was 14.9 weeks. The median EBRT dose was 40 Gy in responders vs. 21 Gy in non-responders, with the difference being significant (p < 0.001). The biologically effective dose (using α/β = 10, BED₁₀) for responders was significantly higher than the BED₁₀ for non-responders (median 48 Gy vs. 26.4 Gy, p < 0.001), and the optimal cut off value to separate the two groups was 36 Gy (p < 0.001). The absence of distant metastasis and the use of concurrent chemotherapy generally showed a better EBRT response (p = 0.079 and p = 0.079, respectively). In the multivariate analysis, BED₁₀ ≥ 36 Gy was the most significant factor associated with EBRT response (p = 0.001). Overall survival (OS) and re-bleeding-free survival was median 12.6 weeks and 14.9 weeks. The responders to EBRT showed superior OS (16.6 vs. 5.1 months, p < 0.001). Neither acute nor chronic toxicities of grade 3 or higher were observed.

Conclusions

EBRT is an effective method for treating tumor bleeding in advanced gastric cancer, and does not induce severe toxicity.