Symptomatic Radiation Pneumonitis in Elderly Patients Receiving Thoracic Irradiation

Quantification of diffuse parenchymal lung disease in non-small cell lung cancer patients with definitive concurrent chemoradiation therapy for predicting radiation pneumonitis

BACKGROUND

We sought to quantify diffuse parenchymal lung disease (DPLD) extent using quantitative computed tomography (CT) analysis and to investigate its association with radiation pneumonitis (RP) development in non-small cell lung cancer (NSCLC) patients receiving definitive concurrent chemoradiation therapy (CCRT).

METHODS

A total of 82 NSCLC patients undergoing definitive CCRT were included in this prospective cohort study. Pretreatment CT scans were analyzed using quantitative CT analysis software. Low-attenuation area (LAA) features based on lung density and texture features reflecting interstitial lung disease (ILD) were extracted from the whole lung. Clinical and dosimetric factors were also evaluated. RP development was assessed using the Common Terminology Criteria for Adverse Events version 5.0. Univariable and multivariable logistic regression analyses were performed to identify independent risk factors for grade ≥3 (≥GR3) RP.

RESULTS

RP was identified in 68 patients (73.9%), with nine patients (10.9%) experiencing ≥GR3 RP. Univariable logistic regression analysis identified excess kurtosis and high-attenuation area (HAA)_volume (cc) as significantly associated with ≥GR3 RP. Multivariable logistic regression analysis showed that the combined use of imaging features and clinical factors (forced expiratory volume in 1 second [FEV1], forced vital capacity [FVC], and CHEMO regimen) demonstrated the best performance (area under the receiver operating characteristic curve = 0.924) in predicting ≥GR3 RP.

CONCLUSION

Quantified imaging features of DPLD obtained from pretreatment CT scans would predict the occurrence of RP in NSCLC patients undergoing definitive CCRT. Combining imaging features with clinical factors could improve the accuracy of the predictive model for severe RP.

Angiotensin converting enzyme (ACE) inhibitors as radiation countermeasures for long-duration space flights

Angiotensin converting enzyme (ACE) inhibitors are effective countermeasures to chronic radiation injuries in rodent models, and there is evidence for similar effects in humans. In rodent models ACE inhibitors are effective mitigators of radiation injury to kidney, lung, central nervous system (CNS) and skin, even when started weeks after irradiation. In humans, the best data for their efficacy as radiation countermeasures comes from retrospective studies of injuries in radiotherapy patients. We propose that ACE inhibitors, at doses approved for human use for other indications, could be used to reduce the risk of chronic radiation injuries from deep-space exploration. Because of the potential interaction of ACE inhibitors and microgravity (due to effects of ACE inhibitors on fluid balance) use might be restricted to post-exposure when/if radiation exposures reached a danger level. A major unresolved issue for this approach is the sparse evidence for the efficacy of ACE inhibitors after low-dose-rate exposure and/or for high-LET radiations (as would occur on long-duration space flights). A second issue is that the lack of a clear mechanism of action of the ACE inhibitors as mitigators makes obtaining an appropriate label under the Food and Drug Administration Animal Rule difficult.

Treatment strategies for locally advanced non-small cell lung cancer in elderly patients: Translating scientific evidence into clinical practice

Treatment of locally advanced NSCLC (LA-NSCLC) is focused on multimodal strategy, including chemotherapy and radiotherapy (in combination or as alternative treatments), followed by surgery in selected cases. Recently, durvalumab consolidation after definitive chemo-radiation has shown a meaningful overall survival benefit. However, it is important to note that elderly patients represent a high proportion of NSCLC population and frailty and comorbidities can significantly limit treatment options. Indeed, elderly patients are under-represented in clinical trials and data to drive treatment selection in this category of patients are scanty. Available data, main issues and controversies on multimodal treatment in elderly LA-NSCLC patients will be reviewed in this paper.

Analysis of related factors of radiation pneumonia caused by precise radiotherapy of esophageal cancer based on random forest algorithm

The precise radiotherapy of esophageal cancer may cause different degrees of radiation damage for lung tissues and cause radioactive pneumonia. However, the occurrence of radioactive pneumonia is related to many factors. To further clarify the correlation between the occurrence of radioactive pneumonia and related factors, a random forest model was used to build a risk prediction model for patients with esophageal cancer undergoing radiotherapy. In this study, we retrospectively reviewed 118 patients with esophageal cancer confirmed by pathology in our hospital. The health characteristics and related parameters of all patients were analyzed, and the predictive effect of radiation pneumonia was discussed using the random forest algorithm. After treatment, 71 patients developed radioactive pneumonia (60.17%). In univariate analyses, age, planning target volume length, Karnofsky performance score (KPS), pulmonary emphysema, with or without chemotherapy, and the ratio of planning target volume to planning gross tumor volume (PTV/PGTV) in mediastinum were significantly associated with radioactive pneumonia (P < 0.05 for each comparison). Multivariate analysis revealed that with or without pulmonary emphysema (OR = 7.491, P = 0.001), PTV/PGTV (OR = 0.205, P = 0.007), and KPS (OR = 0.251, P = 0.011) were independent predictors for radiation pneumonia. The results concluded that the analysis of radiation pneumonia-related factors based on the random forest algorithm could build a mathematical prediction model for the easily obtained data. This algorithm also could effectively analyze the risk factors of radiation pneumonia and formulate the appropriate treatment plan for esophageal cancer.

Radiographic patterns of symptomatic radiation pneumonitis in lung cancer patients: Imaging predictors for clinical severity and outcome

OBJECTIVE

Investigate the spectrum of radiographic patterns of radiation pneumonitis (RP) in lung cancer patients and identify imaging markers for high-grade RP and RP-related death.

METHODS

Eighty-two patients with lung cancer treated with conventional chest radiotherapy who had symptomatic RP were identified from the radiation oncology database. The imaging features of RP were studied for association with high-grade RP (Grade ≥3) and RP-related death (Grade 5).

RESULTS

RP was Grade 2 in 60 (73%), Grade 3 in 15 (18%), and Grade 5 in 7 patients (9%). Lower performance status (p = 0.04), squamous cell histology (p = 0.03), and FEV1 ≤ 2 (p = 0.009) were associated with high-grade pneumonitis. Older age (p = 0.03) and squamous cell histology (p = 0.03) were associated with RP-related death. The CT findings included ground-glass and reticular opacities in all patients, with traction bronchiectasis in 77 (94%) and consolidation in 74 (90%). The most common radiographic pattern of RP was cryptogenic organizing pneumonia (COP) pattern (n = 54), followed by acute interstitial pneumonia (AIP)/acute respiratory distress syndrome (ARDS) pattern (n = 10). Higher extent of lung involvement, diffuse distribution, and AIP/ARDS pattern were associated with high-grade pneumonitis and RP-related death. AIP/ARDS pattern was a significant factor for high-grade pneumonitis (OR:12.62, p = 0.01) in multivariable analyses adjusting for clinical variables.

CONCLUSION

COP pattern was the most common radiographic pattern for symptomatic RP in lung cancer patients. AIP/ARDS pattern was significantly associated with high-grade RP and RP-related deaths, and was an independent marker for high-grade RP. The recognition of the radiographic patterns of RP can help to effectively contribute to patient management.

Daily Lisinopril vs Placebo for Prevention of Chemoradiation-Induced Pulmonary Distress in Patients With Lung Cancer (Alliance MC1221): A Pilot Double-Blind Randomized Trial

PURPOSE

Chemoradiation (CRT) is an integral treatment modality for patients with locally advanced lung cancer. It has been hypothesized that current use of an angiotensin-converting enzyme inhibitor during CRT may be protective for treatment-related lung damage and pneumonitis.

METHODS AND MATERIALS

We conducted a pilot, double-blind, placebo-controlled, randomized trial. Study-eligible patients receiving curative thoracic radiation therapy (RT) were randomly assigned to 20 mg of lisinopril or placebo once daily during and up to 3 months after RT. All patients received concurrent chemotherapy. The primary endpoint was adverse event profiling. Multiple patient-reported outcome (PRO) surveys, including the Lung Cancer Symptom Scale, Function Assessment of Cancer Therapy-Lung, and the European Organisation for Research and Treatment of Cancer Lung Cancer Questionnaire, were applied with a symptom experience questionnaire. Exploratory comparative statistics were used to detect differences between arms with χ² and Kruskal-Wallis testing.

RESULTS

Five institutions enrolled 23 patients. However, accrual was less than expected. Eleven and 12 patients were in the placebo and lisinopril arms, respectively (mean age, 63.5 years; male, 62%). Baseline characteristics were balanced. Eighteen patients (86%) were former or current smokers. The primary endpoint was met; neither arm had grade 3 or higher hypotension, acute kidney injury, allergic reaction (medication-induced cough), or anaphylaxis (medication-related angioedema). Few PRO measures suggested that compared with the placebo arm, patients receiving lisinopril had less cough, less shortness of breath, fewer symptoms from lung cancer, less dyspnea with both walking and climbing stairs, and better overall quality of life (for all, P < .05).

CONCLUSIONS

Although underpowered because of low accrual, our results suggest that there was a clinical signal for safety-and possibly beneficial by limited PRO measures-in concurrently administering lisinopril during thoracic CRT to mitigate or prevent RT-induced pulmonary distress. Our results showed that a definitive, larger-scale, randomized phase 3 trial is needed in the future.

18F-FDG PET/CT in Patients with Parenchymal Changes Attributed to Radiation Pneumonitis

Objectives:

Radiation pneumonitis (RP) can be an adverse complication of radiotherapy (RT) and can limit the application of the already planned radiation dose. It is often associated with RT of lung carcinoma and is occasionally caused by radiation therapy of breast carcinoma and lymphomas located in the mediastinum. Positron emission tomography/computed tomography (PET/CT) emerges lately as a prospective modality for early diagnostics of RP. The aim of this study was to summarize the initial data from diagnostic application of PET/CT in patients suspicious of RP and to derive criteria, which can help differentiate RP from early recurrence of the disease and/or residual tumor.

Methods:

The current study included 23 patients who had metabolic (PET) and anatomical (CT) changes consistent with RP. We additionally defined metabolic activity (SUV_max) in the lung parenchyma of 20 patients without RT.

Results:

All patients had increased metabolic activity in the lung parenchyma involved in the irradiated area with a mean SUV_max 3.45 (ranging between 1 and 7.1). The control group had a physiological background metabolic activity-SUV_max 0.61 +/- 0.11.

Conclusion:

Metabolic changes in patients suspicious of RP involved diffusely increased metabolic activity coinciding with the anatomical changes in the irradiated area. Three out of 23 patients had a proven recurrence of the primary neoplastic process in the irradiated area. The metabolic changes in those patients involved an increase in metabolic activity at follow-up or lack of tendency towards normalization after chemotherapy, which implied the existence of viable tumor cells. Our initial experience in the diagnostic application of ¹⁸F-FDG PET/CT in patients suspicious of RP allows us to summarize the following: PET/CT is a reliable imaging modality in the diagnostics of RP. Through its sequential use, we can differentiate inflammatory changes related to RP from early recurrence of the primary neoplastic process.

The dosimetric effects of limited elective nodal irradiation in volumetric modulated arc therapy treatment planning for locally advanced non-small cell lung cancer

Objective

Contemporary radiotherapy guidelines for locally advanced non-small cell lung carcinoma (LA-NSCLC) recommend omitting elective nodal irradiation, despite the fact that evidence supporting this came primarily from older reports assessing comprehensive nodal coverage using 3D conformal techniques. Herein, we evaluated the dosimetric implications of the addition of limited elective nodal irradiation (LENI) to standard involved field irradiation (IFI) using volumetric modulated arc therapy (VMAT) planning.

Method

Target volumes and organs-at-risk (OARs) were delineated on CT simulation images of 20 patients with LA-NSCLC. Two VMAT plans (IFI and LENI) were generated for each patient. Involved sites were treated to 60 Gy in 30 fractions for both IFI and LENI plans. Adjacent uninvolved nodal regions, considered high risk based on the primary tumor site and extent of nodal involvement, were treated to 51 Gy in 30 fractions in LENI plans using a simultaneous integrated boost approach.

Results

All planning objectives for PTVs and OARs were achieved for both IFI and LENI plans. LENI resulted in significantly higher esophagus D_mean (15.3 vs. 22.5 Gy, p < 0.01), spinal cord D_max (34.9 vs. 42.4 Gy, p = 0.02) and lung D_mean (13.5 vs. 15.9 Gy, p = 0.02), V₂₀ (23.0 vs. 27.9%, p = 0.03), and V₅ (52.6 vs. 59.4%, p = 0.02). No differences were observed in heart parameters. On average, only 32.2% of the high-risk nodal volume received an incidental dose of 51 Gy when untargeted in IFI plans.

Conclusion

The addition of LENI to VMAT plans for LA-NSCLC is feasible, with only modestly increased doses to OARs and marginal expected increase in associated toxicity.

Angiotensin-converting Enzyme Inhibitors Decrease the Incidence of Radiation-induced Pneumonitis Among Lung Cancer Patients: A Systematic Review and Meta-analysis

Background: Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) have been demonstrated to mitigate radiation-induced lung damage in animal models and preclinical studies. Our study aims to evaluate whether ACEIs or ARBs reduce the incidence of radiation-induced pneumonitis (RP) in lung cancer patients.

Methods: Publications were searched from EMBASE, PubMed and Web of Science databases. Seven studies published from April 2000 to August 2016 met inclusion criteria and included 1412 patients in total. Only patients with grade 2 and above pneumonitis within 12 months after radiotherapy were analyzed.

Results: Patients taking ACEIs had a lower risk of developing radiation pneumonitis compared with non-users (OR = 0.46, 95%CI = 0.31-0.67, p < 0.0001). While the use of ARBs couldn't reduce the incidence of RP (OR = 1.42, 95%CI = 0.94-2.14, p = 0.10). Elderly patients (age ≥ 70) benefited more from ACEIs (OR = 0.12, 95%CI = 0.02-0.67, p = 0.02). In addition, smokers were found to have a lower risk of developing RP than non-smokers (OR = 0.49, 95%CI = 0.30-0.81, p = 0.005), but sex and the use of statin or NSAID had no influence on the appearance of RP (p = 0.59, p = 0.70, p = 0.40, respectively).

Conclusions: ACE inhibitors could decrease the incidence of symptomatic RP among lung cancer patients. However, the use of ARBs has a slight trend to develop RP but not above statistical significance. Elderly patients (age ≥ 70) benefited the most from ACEIs.

Renin-Angiotensin System Inhibitors to Mitigate Cancer Treatment-Related Adverse Events

Treatment-related side effects are a major clinical problem in cancer treatment. They lead to reduced compliance to therapy as well as increased morbidity and mortality. Well-known are the sequelae of chemotherapy on the heart, especially in childhood cancer survivors. Therefore, measures to mitigate the adverse events of cancer therapy may improve health and quality of life in patients with cancer, both in the short and long term. The renin-angiotensin system (RAS) affects all hallmarks of cancer, and blockage of the RAS is associated with an improved outcome in several cancer types. There is also increasing evidence that inhibition of the RAS might be able to alleviate or even prevent certain types of cancer treatment-related adverse effects. In this review, we summarize the potential of RAS inhibitors to mitigate cancer treatment-related adverse events, with a special emphasis on chemotherapy-induced cardiotoxicity, radiation injury, and arterial hypertension. Clin Cancer Res; 24(16); 3803-12. ©2018 AACR.

Novel Indications for Commonly Used Medications as Radiation Protectants in Spaceflight

BACKGROUND

In the space environment, the traditional radioprotective principles of time, distance, and shielding become difficult to implement. Additionally, the complex radiation environment inherent in space, the chronic exposure timeframe, and the presence of numerous confounding variables complicate the process of creating appropriate risk models for astronaut exposure. Pharmaceutical options hold tremendous promise to attenuate acute and late effects of radiation exposure in the astronaut population. Pharmaceuticals currently approved for other indications may also offer radiation protection, modulation, or mitigation properties along with a well-established safety profile. Currently there are only three agents which have been clinically approved to be employed for radiation exposure, and these only for very narrow indications. This review identifies a number of agents currently approved by the U.S. Food and Drug Administration (FDA) which could warrant further investigation for use in astronauts. Specifically, we examine preclinical and clinical evidence for statins, nonsteroidal anti-inflammatory drugs (NSAIDs), angiotensin converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), metformin, calcium channel blockers, β adrenergic receptor blockers, fingolimod, N-acetylcysteine, and pentoxifylline as potential radiation countermeasures.McLaughlin MF, Donoviel DB, Jones JA. Novel indications for commonly used medications as radiation protectants in spaceflight. Aerosp Med Hum Perform. 2017; 88(7):665-676.

Pulmonary emphysema is a risk factor for radiation pneumonitis in NSCLC patients with squamous cell carcinoma after thoracic radiation therapy

Pulmonary emphysema (PE) has been demonstrated to have a high prevalence in patients with locally advanced non-small cell lung cancer (NSCLC). A total of 153 patients with locally advanced NSCLC were enrolled in this study to investigate the association between PE and radiation pneumonitis (RP) after definitive thoracic radiation therapy (TRT). The incidence of RP in Grade 2, 3 and 5 were 11.1%, 9.8% and 0.7%, respectively. Univariate analysis revealed that age, PE, forced vital capacity (FVC), arterial partial pressure of oxygen (PO₂) and mean lung dose (MLD) were significantly associated with the risk of Grade ≥2 or Grade ≥3 RP in patients with squamous cell carcinoma (SCC, P < 0.05). Logistic analysis demonstrated that PE was an independent risk factor of RP in SCC (P < 0.05). Receiver operating characteristics (ROC) analysis revealed that the combination of age, PE, FVC, PO₂ and MLD had a higher value to predict RP in SCC (AUC = 0.856 in Grade ≥2 RP and 0.882 in Grade ≥3 RP, respectively). Kaplan-Meier analysis revealed that the more severe the PE, the higher the incidence of RP in SCC. Our results revealed that PE was a high risk factor for locally advanced NSCLC patients followed definitive TRT, especially for SCC patients.

Radical Radiotherapy for Locally Advanced Non-small Cell Lung Cancer: When Should Concurrent Chemoradiotherapy Not Be Used?

Concurrent chemotherapy and radiotherapy confers a significant, but small, benefit for overall survival compared with sequential chemoradiotherapy. The improvement of about 4% with a hazard ratio of 0.85 has only been proven for fit patients with a good organ function. From non-randomised trials, there are no indications that concurrent chemoradiotherapy is clearly superior to the sequential approach in other patients. Moreover, radiotherapy alone can lead to 5 year survival rates of 20%. As the differences in long-term survival between the treatment options are small, even fit patients should be offered, via a shared decision process, the choice between concurrent and non-concurrent chemotherapy and radiotherapy. In less fit patients, sequential chemoradiotherapy offers a chance for long-term survival and cure with less toxicity than the concurrent approach.

[Non-small cell lung cancer irradiation in elderly]

People over the age of 65 are often excluded from participation in oncological clinical trials. However, more than half of patients diagnosed with non-small-cell lung cancer are older than 65 years. Any therapeutic strategy must be discussed in multidisciplinary meetings after adapted geriatric assessment. Patients who benefit from the comprehensive geriatric assessment (CGA) of Balducci and Extermann are those whose G8 screening tool score is less than or equal to 14. Age itself does not contraindicate a curative therapeutic approach. Stereotactic radiotherapy is an alternative to surgery for early stages in elderly patients who are medically inoperable or who refuse surgery, because it significantly increases overall survival. Mostly sequential (rarely concomitant) chemoradiotherapy can be proposed to elderly patients with locally advanced stages in good general state of health. For the others, an exclusive palliative radiotherapy, a single or dual agent of chemotherapy, a targeted drug or best supportive care only may be discussed.

Renin-Angiotensin System Inhibitors Might Help to Reduce the Development of Symptomatic Radiation Pneumonitis After Stereotactic Body Radiotherapy for Lung Cancer

INTRODUCTION

The purpose of the present study was to evaluate the role of renin-angiotensin system (RAS) inhibitors in preventing symptomatic radiation pneumonitis (RP) after stereotactic body radiotherapy (SBRT).

MATERIALS AND METHODS

The data from 158 patients with a solitary lung lesion treated with 1 to 3 fractions of SBRT from December 2008 to July 2014 were retrospectively analyzed. The incidence of RP was evaluated according to the Common Toxicity Criteria for Adverse Events, version 4. The use of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) was analyzed to assess for possible correlations with the development of grade ≥ 2 RP. The patient and dosimetric variables were also assessed.

RESULTS

After a median follow-up period of 13.8 months (range, 3.2-55.0 months), 22 patients had developed grade ≥ 2 RP. Patients with peripheral lesions, favorable dosimetric data, and ACEI and/or ARB use had a reduced risk of symptomatic RP. In unadjusted and adjusted multivariate analyses, ACEI and/or ARB intake and the dosimetric variables were statistically significant factors. In a secondary analysis, the use of ACEIs and ARBs among patients with a greater planning target volume and higher dosimetric values correlated with a reduced risk of symptomatic RP.

CONCLUSION

The use of a RAS inhibitor was associated with a decreased incidence of symptomatic RP among patients undergoing SBRT for lung lesions. Patients with higher dosimetric values had a reduced risk of grade ≥ 2 RP with ACEI and ARB use.

Stereotactic ablative body radiation therapy for tumors in the lung in octogenarians: a retrospective single institution study

Background

Treatment of cancer in the lung in octogenarians is limited by their health and functional status. Stereotactic ablative radiotherapy is an established noninvasive treatment option for medically inoperable patients, with a toxicity profile that may be more tolerable in elderly patients.

Methods

Patients more than 80 years old treated with stereotactic ablative radiotherapy for malignant tumors in the lung between January 2007 and August 2012 at a single institution were identified and retrospectively analyzed for toxicity and survival.

Results

Thirty patients were identified with a total of 32 lesions treated. Patients ranged in age from 80.8 to 90.7 years old (median 84.9) at the time of treatment. Twenty patients had ECOG performance status 0–1, and 10 had performance status 2–3. Stage distribution at treatment was: stage I (20 patients), stage III (1), stage IV (1), and 8 recurrent tumors. Patients were treated to a median total dose of 54 Gy in 3 fractions (range 20–60 Gy in 1 to 5 fractions). Median follow up was 13 months (range 2–60 months). Fifteen patients were still living at last review. There was one failure in field and one failure in the same lobe that was treated. One patient died with progressive regional disease, and four died of progressive metastatic disease. Three patients had late grade 3 pulmonary dyspnea with no grade 4 or 5 toxicities. One patient had late grade 2 pneumonitis, and 3 patients had late grade 1 pneumonitis. Three patients had grade 1 chest wall pain.

Conclusions

Octogenarians tolerated ablative treatment with minimal toxicity. Stereotactic ablative body radiotherapy is an option to consider in treatment of elderly patients.

Molecular mechanisms and treatment of radiation-induced lung fibrosis

Radiation-induced lung fibrosis (RILF) is a severe side effect of radiotherapy in lung cancer patients that presents as a progressive pulmonary injury combined with chronic inflammation and exaggerated organ repair. RILF is a major barrier to improving the cure rate and well-being of lung cancer patients because it limits the radiation dose that is required to effectively kill tumor cells and diminishes normal lung function. Although the exact mechanism is unclear, accumulating evidence suggests that various cells, cytokines and regulatory molecules are involved in the tissue reorganization and immune response modulation that occur in RILF. In this review, we will summarize the general symptoms, diagnostics, and current understanding of the cells and molecular factors that are linked to the signaling networks implicated in RILF. Potential approaches for the treatment of RILF will also be discussed. Elucidating the key molecular mediators that initiate and control the extent of RILF in response to therapeutic radiation may reveal additional targets for RILF treatment to significantly improve the efficacy of radiotherapy for lung cancer patients.