Prognostic Value of Chest CT Findings at BOS Diagnosis in Lung Transplant Recipients

BACKGROUND

Bronchiolitis obliterans syndrome (BOS) after lung transplantation is characterized by fibrotic small airway remodeling, recognizable on high-resolution computed tomography (HRCT). We studied the prognostic value of key HRCT features at BOS diagnosis after lung transplantation.

METHODS

The presence and severity of bronchiectasis, mucous plugging, peribronchial thickening, parenchymal anomalies, and air trapping, summarized in a total severity score, were assessed using a simplified Brody II scoring system on HRCT at BOS diagnosis, in a cohort of 106 bilateral lung transplant recipients transplanted between January 2004 and January 2016. Obtained scores were subsequently evaluated regarding post-BOS graft survival, spirometric parameters, and preceding airway infections.

RESULTS

A high total Brody II severity score at BOS diagnosis (P = 0.046) and high subscores for mucous plugging (P = 0.0018), peribronchial thickening (P = 0.0004), or parenchymal involvement (P = 0.0121) are related to worse graft survival. A high total Brody II score was associated with a shorter time to BOS onset (P = 0.0058), lower forced expiratory volume in 1 s (P = 0.0006) forced vital capacity (0.0418), more preceding airway infections (P = 0.004), specifically with Pseudomonas aeruginosa (P = 0.002), and increased airway inflammation (P = 0.032).

CONCLUSIONS

HRCT findings at BOS diagnosis after lung transplantation provide additional information regarding its underlying pathophysiology and for future prognosis of graft survival.

ERS/ESTS/ESTRO/ESR/ESTI/EFOMP statement on management of incidental findings from low dose CT screening for lung cancer

BACKGROUND

Screening for lung cancer with low radiation dose computed tomography has a strong evidence base, is being introduced in several European countries and is recommended as a new targeted cancer screening programme. The imperative now is to ensure that implementation follows an evidence-based process that will ensure clinical and cost effectiveness. This European Respiratory Society (ERS) task force was formed to provide an expert consensus for the management of incidental findings which can be adapted and followed during implementation.

METHODS

A multi-European society collaborative group was convened. 23 topics were identified, primarily from an ERS statement on lung cancer screening, and a systematic review of the literature was conducted according to ERS standards. Initial review of abstracts was completed and full text was provided to members of the group for each topic. Sections were edited and the final document approved by all members and the ERS Science Council.

RESULTS

Nine topics considered most important and frequent were reviewed as standalone topics (interstitial lung abnormalities, emphysema, bronchiectasis, consolidation, coronary calcification, aortic valve disease, mediastinal mass, mediastinal lymph nodes and thyroid abnormalities). Other topics considered of lower importance or infrequent were grouped into generic categories, suitable for general statements.

CONCLUSIONS

This European collaborative group has produced an incidental findings statement that can be followed during lung cancer screening. It will ensure that an evidence-based approach is used for reporting and managing incidental findings, which will mean that harms are minimised and any programme is as cost-effective as possible.

ERS/ESTS/ESTRO/ESR/ESTI/EFOMP statement on management of incidental findings from low dose CT screening for lung cancer

BACKGROUND

Screening for lung cancer with low radiation dose computed tomography has a strong evidence base, is being introduced in several European countries and is recommended as a new targeted cancer screening programme. The imperative now is to ensure that implementation follows an evidence-based process that will ensure clinical and cost effectiveness. This European Respiratory Society (ERS) task force was formed to provide an expert consensus for the management of incidental findings which can be adapted and followed during implementation.

METHODS

A multi-European society collaborative group was convened. 23 topics were identified, primarily from an ERS statement on lung cancer screening, and a systematic review of the literature was conducted according to ERS standards. Initial review of abstracts was completed and full text was provided to members of the group for each topic. Sections were edited and the final document approved by all members and the ERS Science Council.

RESULTS

Nine topics considered most important and frequent were reviewed as standalone topics (interstitial lung abnormalities, emphysema, bronchiectasis, consolidation, coronary calcification, aortic valve disease, mediastinal mass, mediastinal lymph nodes and thyroid abnormalities). Other topics considered of lower importance or infrequent were grouped into generic categories, suitable for general statements.

CONCLUSIONS

This European collaborative group has produced an incidental findings statement that can be followed during lung cancer screening. It will ensure that an evidence-based approach is used for reporting and managing incidental findings, which will mean that harms are minimised and any programme is as cost-effective as possible.

Single-cell transcriptomics identifies pathogenic T-helper 17.1 cells and pro-inflammatory monocytes in immune checkpoint inhibitor-related pneumonitis

Background

Immune checkpoint inhibitor (ICI)-related pneumonitis is the most frequent fatal immune-related adverse event associated with programmed cell death protein-1/programmed death ligand-1 blockade. The pathophysiology however remains largely unknown, owing to limited and contradictory findings in existing literature pointing at either T-helper 1 or T-helper 17-mediated autoimmunity. In this study, we aimed to gain novel insights into the mechanisms of ICI-related pneumonitis, thereby identifying potential therapeutic targets.

Methods

In this prospective observational study, single-cell RNA and T-cell receptor sequencing was performed on bronchoalveolar lavage fluid of 11 patients with ICI-related pneumonitis and 6 demographically-matched patients with cancer without ICI-related pneumonitis. Single-cell transcriptomic immunophenotyping and cell fate mapping coupled to T-cell receptor repertoire analyses were performed.

Results

We observed enrichment of both CD4+ and CD8+ T cells in ICI-pneumonitis bronchoalveolar lavage fluid. The CD4+ T-cell compartment showed an increase of pathogenic T-helper 17.1 cells, characterized by high co-expression of TBX21 (encoding T-bet) and RORC (ROR-γ), IFN-G (IFN-γ), IL-17A, CSF2 (GM-CSF), and cytotoxicity genes. Type 1 regulatory T cells and naïve-like CD4+ T cells were also enriched. Within the CD8+ T-cell compartment, mainly effector memory T cells were increased. Correspondingly, myeloid cells in ICI-pneumonitis bronchoalveolar lavage fluid were relatively depleted of anti-inflammatory resident alveolar macrophages while pro-inflammatory ‘M1-like’ monocytes (expressing TNF, IL-1B, IL-6, IL-23A, and GM-CSF receptor CSF2RA, CSF2RB) were enriched compared with control samples. Importantly, a feedforward loop, in which GM-CSF production by pathogenic T-helper 17.1 cells promotes tissue inflammation and IL-23 production by pro-inflammatory monocytes and vice versa, has been well characterized in multiple autoimmune disorders but has never been identified in ICI-related pneumonitis.

Conclusions

Using single-cell transcriptomics, we identified accumulation of pathogenic T-helper 17.1 cells in ICI-pneumonitis bronchoalveolar lavage fluid—a phenotype explaining previous divergent findings on T-helper 1 versus T-helper 17 involvement in ICI-pneumonitis—, putatively engaging in detrimental crosstalk with pro-inflammatory ‘M1-like’ monocytes. This finding yields several novel potential therapeutic targets for the treatment of ICI-pneumonitis. Most notably repurposing anti-IL-23 merits further research as a potential efficacious and safe treatment for ICI-pneumonitis.

Lung Aeration in COVID-19 Pneumonia by Ultrasonography and Computed Tomography

We conducted a prospective single-center observational study to determine lung ultrasound reliability in assessing global lung aeration in 38 hospitalized patients with non-critical COVID-19. On admission, fixed chest CT scans using visual (CTv) and software-based (CTs) analyses along with lung ultrasound imaging protocols and scoring systems were applied. The primary endpoint was the correlation between global chest CTs score and global lung ultrasound score. The secondary endpoint was the association between radiographic features and clinical disease classification or laboratory indices of inflammation. Bland−Altman analysis between chest CT scores obtained visually (CTv) or using software (CTs) indicated that only 1 of the 38 paired measures was outside the 95% limits of agreement (−4 to +4 score). Global lung ultrasound score was highly and positively correlated with global software-based CTs score (r = 0.74, CI = 0.55−0.86; p < 0.0001). Significantly higher median CTs score (p = 0.01) and lung ultrasound score (p = 0.02) were found in severe compared to moderate COVID-19. Furthermore, we identified significantly lower (p < 0.05) lung ultrasound and CTs scores in those patients with a more severe clinical condition manifested by SpO2 < 92% and C-reactive protein > 58 mg/L. We concluded that lung ultrasound is a reliable bedside clinical tool to assess global lung aeration in hospitalized non-critical care patients with COVID-19 pneumonia.

Value of [68Ga]Ga-somatostatin receptor PET/CT in the grading of pulmonary neuroendocrine (carcinoid) tumours and the detection of disseminated disease: single-centre pathology-based analysis and review of the literature

BACKGROUND

Although most guidelines suggest performing a positron emission tomography/computed tomography (PET/CT) with somatostatin receptor (SSTR) ligands for staging of pulmonary carcinoid tumours (PC), only a limited number of studies have evaluated the role of this imaging tool in this specific patient population. The preoperative differentiation between typical carcinoid (TC) and atypical carcinoid (AC) and the extent of dissemination (N/M status) are crucial factors for treatment allocation and prognosis of these patients. Therefore, we performed a pathology-based retrospective analysis of the value of SSTR PET/CT in tumour grading and detection of nodal and metastatic involvement of PC and compared this with the previous literature and with [¹⁸F]FDG PET/CT in a subgroup of patients.

METHODS

SSTR PET/CT scans performed between January 2007 and May 2020 in the context of PC were included. If available, [¹⁸F]FDG PET/CT images were also evaluated. The maximum standardized uptake (SUV_max) values of the primary tumour, of the pathologically examined hilar and mediastinal lymph node stations, as well as of the distant metastases, were recorded. Tumoural SUV_max values were related to the tumour type (TC versus AC) for both SSTR and [¹⁸F]FDG PET/CT in diagnosing and differentiating both tumour types. Nodal SUV_max values were compared to the pathological status (N⁺ versus N^-) to evaluate the diagnostic accuracy of SSTR PET/CT in detecting lymph node involvement. Finally, a mixed model analysis of all pathologically proven distant metastatic lesions was performed.

RESULTS

A total of 86 SSTR PET/CT scans performed in 86 patients with PC were retrospectively analysed. [¹⁸F]FDG PET/CT was available in 46 patients. Analysis of the SUV_max values in the primary tumour showed significantly higher SSTR uptake in TC compared with AC (median SUV_max 18.4 vs 3.8; p = 0.003) and significantly higher [¹⁸F]FDG uptake in AC compared to TC (median SUV_max 5.4 vs 3.5; p = 0.038). Receiver operating characteristic (ROC) curve analysis resulted in an area under the curve (AUC) of 0.78 for the detection of TC on SSTR PET/CT and of 0.73 for the detection of AC on [¹⁸F]FDG PET/CT. A total of 267 pathologically evaluated hilar and mediastinal lymph node stations were analysed. ROC analysis of paired SSTR/[¹⁸F]FDG SUV_max values for the detection of metastasis of TC in 83 lymph node stations revealed an AUC of 0.91 for SSTR PET/CT and of 0.74 for [¹⁸F]FDG PET/CT (difference 0.17; 95% confidence interval - 0.03 to 0.38; p = 0.10). In a sub-cohort of 10 patients with 12 distant lesions that were pathologically examined due to a suspicious aspect on SSTR PET/CT, a positive predictive value (PPV) of 100% was observed.

CONCLUSION

Our findings confirm the higher SSTR ligand uptake in TC compared to AC and vice versa for [¹⁸F]FDG uptake. More importantly, we found a good diagnostic performance of SSTR PET/CT for the detection of hilar and mediastinal lymph node metastases of TC. Finally, a PPV of 100% for SSTR PET/CT was found in a small sub-cohort of patients with pathologically investigated distant metastatic lesions. Taken together, SSTR PET/CT has a very high diagnostic value in the TNM assessment of pulmonary carcinoids, particularly in TC, which underscores its position in European guidelines.

Prospective longitudinal evaluation of hospitalised COVID-19 survivors 3 and 12 months after discharge

Background

Long-term outcome data of coronavirus disease 2019 (COVID-19) survivors are needed to understand their recovery trajectory and additional care needs.

Methods

A prospective observational multicentre cohort study was carried out of adults hospitalised with COVID-19 from March through May 2020. Workup at 3 and 12 months following admission consisted of clinical review, pulmonary function testing, 6-min walk distance (6MWD), muscle strength, chest computed tomography (CT) and quality of life questionnaires. We evaluated factors correlating with recovery by linear mixed effects modelling.

Results

Of 695 patients admitted, 299 and 226 returned at 3 and 12 months, respectively (median age 59 years, 69% male, 31% severe disease). About half and a third of the patients reported fatigue, dyspnoea and/or cognitive impairment at 3 and 12 months, respectively. Reduced 6MWD and quadriceps strength were present in 20% and 60% at 3 months versus 7% and 30% at 12 months. A high anxiety score and body mass index correlated with poor functional recovery. At 3 months, diffusing capacity for carbon monoxide (D_LCO) and total lung capacity were below the lower limit of normal in 35% and 18%, decreasing to 21% and 16% at 12 months; predictors of poor D_LCO recovery were female sex, pre-existing lung disease, smoking and disease severity. Chest CT improved over time; 10% presented non-progressive fibrotic changes at 1 year.

Conclusion

Many COVID-19 survivors, especially those with severe disease, experienced limitations at 3 months. At 1 year, the majority showed improvement to almost complete recovery. To identify additional care or rehabilitation needs, we recommend a timely multidisciplinary follow-up visit following COVID-19 admission.

Most hospitalised #COVID19 survivors show promising recovery 1 year after discharge, although mild symptoms may linger. Severe impairments are rare, but this study suggests an evaluation of the individual care needs after discharge.https://bit.ly/3sZK45x

Radiological findings in low-dose CT for COVID-19 pneumonia in 182 patients: Correlation of signs and severity with patient outcome

To characterize computed tomography (CT) findings of coronavirus disease 2019 (COVID-19) pneumonia and their value in outcome prediction.Chest CTs of 182 patients with a confirmed diagnosis of COVID-19 infection by real-time reverse transcription polymerase chain reaction were evaluated for the presence of CT-abnormalities and their frequency. Regarding the patient outcome each patient was categorized in 5 progressive stages and the duration of hospitalization was determined. Regression analysis was performed to find which CT findings are predictive for patient outcome and to assess prognostic factors for the hospitalization duration.Multivariate statistical analysis confirmed a higher age (OR = 1.023, P  =  .025), a higher total visual severity score (OR = 1.038, P  =  .002) and the presence of crazy paving (OR = 2.160, P  =  .034) as predictive parameters for patient outcome. A higher total visual severity score (+0.134 days; P  =  .012) and the presence of pleural effusion (+13.985 days, P  =  0.005) were predictive parameters for a longer hospitalization duration. Moreover, a higher sensitivity of chest CT (false negatives 10.4%; true positives 78.6%) in comparison to real-time reverse transcription polymerase chain reaction was obtained.An increasing percentage of lung opacity as well as the presence of crazy paving and a higher age are associated with a worse patient outcome. The presence of a higher total visual severity score and pleural effusion are significant predictors for a longer hospitalization duration. These results are underscoring the value of chest CT as a diagnostic and prognostic tool in the pandemic outbreak of COVID-19, to facilitate fast detection and to preserve the limited (intensive) care capacity only for the most vulnerable patients.

Detection of pulmonary nodules with scoutless fixed-dose ultra-low-dose CT: a prospective study

OBJECTIVES

To determine the accuracy of scoutless, fixed-dose ultra-low-dose (ULD) CT compared to standard-dose (SD) CT for pulmonary nodule detection and semi-automated nodule measurement, across different patient sizes.

METHODS

Sixty-three patients underwent ULD and SD CT. Two readers examined all studies visually and with computer-aided detection (CAD). Nodules detected on SD CT were included in the reference standard by consensus and stratified into 4 categories (nodule category, NODCAT) from the Dutch-Belgian Lung Cancer Screening trial (NELSON). Effects of NODCAT and patient size on nodule detection were determined. For each nodule, volume and diameter were compared between both scans.

RESULTS

The reference standard comprised 173 nodules. For both readers, detection rates on ULD versus SD CT were not significantly different for NODCAT 3 and 4 nodules > 50 mm³ (reader 1: 93% versus 89% (p = 0.257); reader 2: 96% versus 98% (p = 0.317)). For NODCAT 1 and 2 nodules < 50 mm³, detection rates on ULD versus SD CT dropped significantly (reader 1: 66% versus 80% (p = 0.023); reader 2: 77% versus 87% (p = 0.039)). Body mass index and chest circumference did not influence nodule detectability (p = 0.229 and p = 0.362, respectively). Calculated volumes and diameters were smaller on ULD CT (p < 0.0001), without altering NODCAT (84% agreement).

CONCLUSIONS

Scoutless ULD CT reliably detects solid lung nodules with a clinically relevant volume (> 50 mm³) in lung cancer screening, irrespective of patient size. Since detection rates were lower compared to SD CT for nodules < 50 mm³, its use for lung metastasis detection should be considered on a case-by-case basis.

KEY POINTS

• Detection rates of pulmonary nodules > 50 mm³are not significantly different between scoutless ULD and SD CT (i.e. volumes clinically relevant in lung cancer screening based on the NELSON trial), but were different for the detection of nodules < 50 mm³(i.e. volumes still potentially relevant in lung metastasis screening). • Calculated nodule volumes were on average 0.03 mL or 9% smaller on ULD CT, which is below the 20-25% interscan variability previously reported with software-based volumetry. • Even though a scoutless, fixed-dose ULD CT protocol was used (CTDI_vol0.15 mGy), pulmonary nodule detection was not influenced by patient size.

Comparing Visual Scoring of Lung Injury with a Quantifying AI-Based Scoring in Patients with COVID-19

OBJECTIVES

Fast diagnosis of Coronavirus Disease 2019 (COVID-19), and the detection of high-risk patients are crucial but challenging in the pandemic outbreak. The aim of this study was to evaluate if deep learning-based software correlates well with the generally accepted visual-based scoring for quantification of the lung injury to help radiologist in triage and monitoring of COVID-19 patients.

MATERIALS AND METHODS

In this retrospective study, the lobar analysis of lung opacities (% opacities) by means of a prototype deep learning artificial intelligence (AI)-based software was compared to visual scoring. The visual scoring system used five categories (0: 0%, 1: 0-5%, 2: 5-25%, 3: 25-50%, 4: 50-75% and 5: >75% involvement). The total visual lung injury was obtained by the sum of the estimated grade of involvement of each lobe and divided by five.

RESULTS

The dataset consisted of 182 consecutive confirmed COVID-19 positive patients with a median age of 65 ± 16 years, including 110 (60%) men and 72 (40%) women. There was a correlation coefficient of 0.89 (p < 0.001) between the visual and the AI-based estimates of the severity of lung injury.

CONCLUSION

The study indicates a very good correlation between the visual scoring and AI-based estimates of lung injury in COVID-19.

Discriminating mild from critical COVID-19 by innate and adaptive immune single-cell profiling of bronchoalveolar lavages

How the innate and adaptive host immune system miscommunicate to worsen COVID-19 immunopathology has not been fully elucidated. Here, we perform single-cell deep-immune profiling of bronchoalveolar lavage (BAL) samples from 5 patients with mild and 26 with critical COVID-19 in comparison to BALs from non-COVID-19 pneumonia and normal lung. We use pseudotime inference to build T-cell and monocyte-to-macrophage trajectories and model gene expression changes along them. In mild COVID-19, CD8⁺ resident-memory (T_RM) and CD4⁺ T-helper-17 (T_H17) cells undergo active (presumably antigen-driven) expansion towards the end of the trajectory, and are characterized by good effector functions, while in critical COVID-19 they remain more naïve. Vice versa, CD4⁺ T-cells with T-helper-1 characteristics (T_H1-like) and CD8⁺ T-cells expressing exhaustion markers (T_EX-like) are enriched halfway their trajectories in mild COVID-19, where they also exhibit good effector functions, while in critical COVID-19 they show evidence of inflammation-associated stress at the end of their trajectories. Monocyte-to-macrophage trajectories show that chronic hyperinflammatory monocytes are enriched in critical COVID-19, while alveolar macrophages, otherwise characterized by anti-inflammatory and antigen-presenting characteristics, are depleted. In critical COVID-19, monocytes contribute to an ATP-purinergic signaling-inflammasome footprint that could enable COVID-19 associated fibrosis and worsen disease-severity. Finally, viral RNA-tracking reveals infected lung epithelial cells, and a significant proportion of neutrophils and macrophages that are involved in viral clearance.

Performance of Low-Dose Chest CT as a Triage Tool for Suspected COVID-19 Patients

PURPOSE

To investigate the role of low-dose chest computed tomography (CT) imaging in the triage of patients suspected of coronavirus disease 2019 (COVID-19) in an emergency setting.

MATERIALS AND METHODS

Data from 610 patients admitted to our emergency unit from March 20, 2020, until April 11, 2020, with suspicion of COVID-19 were collected. Diagnostic values of low-dose chest CT for COVID-19 were calculated using consecutive reverse-transcription polymerase chain reaction (RT-PCR) tests and bronchoalveolar lavage (BAL) as reference. Comparative analysis of the 199 COVID-19 positive versus 411 COVID-19 negative patients was done with identification of risk factors and predictors of worse outcome.

RESULTS

Sensitivity and specificity of low-dose CT for the diagnosis of COVID-19 respectively ranged from 75% (150/199) to 88% (175/199) and 94% (386/411) to 99% (386/389), depending on the inclusion of inconclusive results. On multivariate analysis, a higher body mass index (BMI), fever, and dyspnea on admission were risk factors for COVID-19 (all p-values < 0.05). The mortality rate was 12.6% (25/199). Higher age and high levels of C-reactive protein (CRP) and D-dimers were predictors of worse outcome (all p-values < 0.05).

CONCLUSION

Low-dose chest CT has a high specificity and a moderate to high sensitivity in symptomatic patients with suspicion of COVID-19 and could be used as an effective tool in setting of triage in high-prevalence areas.

Methodology to create 3D models of COVID-19 pathologies for virtual clinical trials

Purpose: We describe the creation of computational models of lung pathologies indicative of COVID-19 disease. The models are intended for use in virtual clinical trials (VCT) for task-specific optimization of chest x-ray (CXR) imaging. Approach: Images of COVID-19 patients confirmed by computed tomography were used to segment areas of increased attenuation in the lungs, all compatible with ground glass opacities and consolidations. Using a modeling methodology, the segmented pathologies were converted to polygonal meshes and adapted to fit the lungs of a previously developed polygonal mesh thorax phantom. The models were then voxelized with a resolution of 0.5 × 0.5 × 0.5    mm 3 and used as input in a simulation framework to generate radiographic images. Primary projections were generated via ray tracing while the Monte Carlo transport code was used for the scattered radiation. Realistic sharpness and noise characteristics were also simulated, followed by clinical image processing. Example images generated at 120 kVp were used for the validation of the models in a reader study. Additionally, images were uploaded to an Artificial Intelligence (AI) software for the detection of COVID-19. Results: Nine models of COVID-19 associated pathologies were created, covering a range of disease severity. The realism of the models was confirmed by experienced radiologists and by dedicated AI software. Conclusions: A methodology has been developed for the rapid generation of realistic 3D models of a large range of COVID-19 pathologies. The modeling framework can be used as the basis for VCTs for testing detection and triaging of COVID-19 suspected cases.

Assembly 14: clinical techniques, imaging and endoscopy

Assembly 14 (clinical techniques, imaging and endoscopy) is the youngest assembly of the European Respiratory Society (ERS). Because the increasing role of interventional pulmonology in diagnosis and treatment, and the role of imaging as key element in the diagnosis of many diseases, these two groups were growing, and the moment came that they became a new assembly. Assembly 14 accommodates the following groups.

Meet @EuroRespSoc Assembly 14: clinical techniques, imaging and endoscopyhttp://bit.ly/2oAf65R

An unusual presentation of a more common disease entity

A 66-year-old, male patient with a 10-pack-year history of smoking was referred to the internal medicine consultation because of a 4-week history of fatigue, weakness, intermittent low-grade fever, appetite and weight loss, and a mild dry cough. His previous history was unremarkable and his physical examination was normal. Routine laboratory screening revealed leukocytosis (11.08×10⁹ leukocytes per L), elevated C-reactive protein (72.1 mg⋅L⁻¹) and erythrocyte sedimentation rate 57 mm⋅h⁻¹. Analyses for rheumatoid factor, antinuclear antibodies, and cytoplasmic and perinuclear anti-neutrophil cytoplasmic antibodies were all negative. Pulmonary function tests (static and dynamic volumes, flow–volume curve, and lung diffusion capacity) were within the predictive values. Chest radiography demonstrated bilateral hilar enlargement. The patient subsequently underwent a computed tomography (CT) scan of the chest (figure 1).

Beware unusual presentations of more common disease entities, as in this interactive case reporthttp://ow.ly/qj7f30eVFsp

Is there a different dose-effect relation between the primary tumor and involved lymph nodes in locally advanced non-small-cell lung cancer? A hypothesis-generating study

PURPOSE

It is unknown whether the dose-response relation of the primary tumor in NSCLC is different from that of the involved lymph nodes (LN). As the recurrence rate is much lower in LN, we hypothesized that LN need a lower radiation dose.

MATERIAL AND METHODS

A retrospective analysis of prospective data was performed on patients with locally advanced NSCLC treated with (chemo)radiotherapy. The impact of EQD_2,T prescription dose on relapse was analyzed using Cox regression modeling correcting for baseline diameter.

RESULTS

From 2006 to 2010, 75 consecutive patients were included, resulting in 142 lymph nodes in the analysis. Any relapse (locoregional/distant) occurred in 58 patients (77%), while involved nodal relapse (INR) was observed in 13% of patients. No dose-response relationship was observed for INR (p = .22). Primary tumor progression was seen in 40% of patients together with a significant dose-response relationship (p = .033). Baseline nodal diameter was not associated with INR (p = .76), while primary tumor diameter was a highly significant predictor for relapse (p = .0031).

CONCLUSIONS

These results suggest that LN control may be achieved at lower radiation doses than needed for the primary tumor. Prospective dose de-escalation studies on LN are warranted to decrease the incidence of severe esophagitis without compromising local tumor control.

Thin-Section CT Features of Idiopathic Pulmonary Fibrosis Correlated with Micro-CT and Histologic Analysis

Purpose To elucidate the underlying lung changes responsible for the computed tomographic (CT) features of idiopathic pulmonary fibrosis (IPF) and to gain insight into the way IPF proceeds through the lungs and progresses over time. Materials and Methods Micro-CT studies of tissue cores obtained from explant lungs were examined and were correlated 1:1 with a CT study obtained immediately before transplantation. Samples for histologic analysis were obtained from selected cores. Results In areas with no or minimal abnormalities on CT images, small areas of increased attenuation located in or near the interlobular septa can be seen on micro-CT studies. In more involved lung areas, the number of opacities increases and opacities enlarge and approach each other along the interlobular septa, causing a fine reticular pattern on CT images. Simultaneously, air-containing structures in and around these opacities arise, corresponding with small cysts on CT images. Honeycombing is caused by a progressive increase in the number and size of these cystic structures and tissue opacities that gradually extend toward the centrilobular region and finally replace the entire lobule. At histologic analysis, the small islands of increased attenuation very likely correspond with fibroblastic foci. Near these fibroblastic foci, an abnormal adjacency of alveolar walls was seen, suggesting alveolar collapse. In later stages, normal lung tissue is replaced by a large amount of young collagen, as seen in patients with advanced fibrosis. Conclusion Fibrosis and cyst formation in patients with IPF seem to start at the periphery of the pulmonary lobule and progressively extend toward the core of this anatomic lung unit. Evidence was found that alveolar collapse might already be present in an early stage when there is only little pulmonary fibrosis. ^© RSNA, 2016.

Selective mediastinal node irradiation in non-small cell lung cancer in the IMRT/VMAT era: How to use E(B)US-NA information in addition to PET-CT for delineation?

BACKGROUND

FDG-PET-CT-based selective lymph node (LN) irradiation is standard using 3D-conformal techniques for locally advanced NSCLC. With newer techniques (intensity-modulated/volumetric-arc therapy (IMRT/VMAT)), the dose to non-involved adjacent LN decreases, which raises the question whether FDG-PET-CT-delineation is still safe. We therefore evaluated the impact of adding linear endosonography with needle aspiration (E(B)US-NA) to FDG-PET-CT in selective nodal irradiation.

METHODS

Based on literature data on sensitivity and specificity of E(B)US-NA in FDG-PET-CT-staged NSCLC, false negative (FN) rates for different constellations of CT, PET and E(B)US-NA were calculated. The algorithm was tested on consecutive patients with N2/N3 disease referred for radiotherapy in Leuven and Maastricht.

RESULTS

An algorithm determining when to include LN in the GTV is proposed, based on data from 5 meta-analyses. Adding E(B)US-NA to FDG-PET-CT decreases the FN-rate, but for PET-positive and E(B)US-negative LN, FN rates are still 14-16%. In Leuven 520 LN were analyzed, in Maastricht 364 LN; with E(B)US-NA a geographical miss was avoided in 2 (2/40=5%) and 1 (1/28=4%) patients, respectively.

CONCLUSIONS

E(B)US-NA in addition to FDG-PET-CT for mediastinal staging decreases the risk of a geographical miss with 4-5%. The impact of this small decrease on survival is unknown. The proposed algorithm may guide the radiation oncologist when to include LN in the nodal GTV.

Predictors of survival in restrictive chronic lung allograft dysfunction after lung transplantation

BACKGROUND

Chronic lung allograft dysfunction (CLAD) is the main factor limiting long-term survival after lung transplantation. Besides bronchiolitis obliterans syndrome, a restrictive phenotype of CLAD (rCLAD) exists, which is associated with poor prognosis after diagnosis. However, survival determinants for rCLAD remain to be elucidated. Our aim in this study was to establish parameters predicting survival in patients with rCLAD.

METHODS

All patients diagnosed with rCLAD in 2 lung transplant centers were assessed in a retrospective manner. Various clinical parameters [demography, pulmonary function, bronchoalveolar lavage (BAL), histopathology, radiology and blood differentials] at rCLAD diagnosis were correlated with graft survival using unadjusted and adjusted analysis.

RESULTS

A total of 53 patients with rCLAD were included with a median graft survival after diagnosis of 1.1 years. Univariate analysis demonstrated that lower-lobe-dominant or diffuse infiltrates on chest computed tomography, presence of an identifiable trigger before rCLAD onset, lymphocytic bronchiolitis, increased BAL neutrophilia, increased BAL eosinophilia and increased blood eosinophils were associated with inferior graft survival after rCLAD diagnosis. Multivariate analysis confirmed the association of location of infiltrates and blood eosinophilia on graft survival.

CONCLUSION

In this study we have identified parameters associated with graft survival after rCLAD diagnosis that may be useful to predict prognosis.

Tuberculosis infection following anti-TNF therapy in inflammatory bowel disease, despite negative screening

We present two patients with inflammatory bowel disease who, despite negative tuberculosis screening, developed a de novo tuberculosis infection after the start of anti tumor necrosis factor alpha treatment. We discuss current screening methods and their limitations, the approach after positive screening and the timing to resume anti-TNFα treatment after TB infection. We shortly mention the immune reconstitution inflammatory syndrome (IRIS), described in a few cases after the stop of anti-TNFalpha while treating the tuberculosis infection. We conclude with some remaining questions concerning tuberculosis in IBD patients.

A porcine model of acute lung injury by instillation of gastric fluid

BACKGROUND

About 15% of donor lungs are declined because of aspiration contributing to current organ shortage. The aim was to develop a porcine lung injury model by gastric juice (GJ) instillation to study different pretransplant treatment strategies.

MATERIALS AND METHODS

Pigs (n = 6/group) were anesthetized and monitored. At T0 bronchoalveolar lavage (BAL) was performed followed by instillation of 4 mL/kg GJ or saline solution (SAL). Hemodynamics, aerodynamics and oxygenation were recorded for two hours. Serum samples were collected. At T120 a second BAL was performed. CT scans of explanted, inflated lungs were taken, tissue samples were collected and wet/dry weight ratio (W/D) was calculated. Pepsin and bile acids were measured in BAL. IL-8, CRP and MMP-9 were measured in serum and in BAL.

RESULT

Oxygenation and lung compliance was lower in [GJ] versus [SAL] (P < 0.01 and P < 0.001, respectively). More consolidation areas were noticed on CT in GJ versus SAL (P < 0.01). Hemorrhage, edema and neutrophil inflammation were seen on histology in [GJ] (P < 0.01, P < 0.001, P < 0.001, respectively). BAL neutrophils, pepsin, bile acids, and IL-8 (P < 0.05) increased in [GJ]. W/D was higher in [GJ] versus SAL (P < 0.001).

CONCLUSION

Instillation of GJ in pig lungs caused acute lung injury with impaired oxygenation and increased inflammation in BAL, on histology, and on imaging. This model holds promise to assess the efficacy of a broad range of treatment strategies including ex vivo lung perfusion (EVLP).

Intensity-modulated radiotherapy for locally advanced non-small-cell lung cancer: a dose-escalation planning study

PURPOSE

To evaluate the potential for dose escalation with intensity-modulated radiotherapy (IMRT) in positron emission tomography-based radiotherapy planning for locally advanced non-small-cell lung cancer (LA-NSCLC).

METHODS AND MATERIALS

For 35 LA-NSCLC patients, three-dimensional conformal radiotherapy and IMRT plans were made to a prescription dose (PD) of 66 Gy in 2-Gy fractions. Dose escalation was performed toward the maximal PD using secondary endpoint constraints for the lung, spinal cord, and heart, with de-escalation according to defined esophageal tolerance. Dose calculation was performed using the Eclipse pencil beam algorithm, and all plans were recalculated using a collapsed cone algorithm. The normal tissue complication probabilities were calculated for the lung (Grade 2 pneumonitis) and esophagus (acute toxicity, grade 2 or greater, and late toxicity).

RESULTS

IMRT resulted in statistically significant decreases in the mean lung (p <.0001) and maximal spinal cord (p = .002 and 0005) doses, allowing an average increase in the PD of 8.6-14.2 Gy (p ≤.0001). This advantage was lost after de-escalation within the defined esophageal dose limits. The lung normal tissue complication probabilities were significantly lower for IMRT (p <.0001), even after dose escalation. For esophageal toxicity, IMRT significantly decreased the acute NTCP values at the low dose levels (p = .0009 and p <.0001). After maximal dose escalation, late esophageal tolerance became critical (p <.0001), especially when using IMRT, owing to the parallel increases in the esophageal dose and PD.

CONCLUSION

In LA-NSCLC, IMRT offers the potential to significantly escalate the PD, dependent on the lung and spinal cord tolerance. However, parallel increases in the esophageal dose abolished the advantage, even when using collapsed cone algorithms. This is important to consider in the context of concomitant chemoradiotherapy schedules using IMRT.

Aggressive and indolent non-Hodgkin's lymphoma: Response assessment by Integrated International Workshop Criteria

Until recently, response assessment in patients with lymphoma was primarily performed by computed tomography (CT). Based on CT, International Workshop Criteria (IWC) were developed and widely used. Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) is a more sensitive and specific imaging technique for the detection of residual disease in lymphoma, and Revised Integrated International Workshop Criteria (IWC + PET) were recently proposed by the members of the International Harmonization Project (IHP), which combine both imaging techniques. We determined whether these new IWC + PET-criteria, can more accurately predict outcome compared to IWC-criteria in aggressive and indolent non-Hodgkin's lymphoma (NHL), and therefore correlated IWC and IWC + PET response with time-to-next-treatment (TNT) in 69 patients with NHL. We demonstrated that IWC + PET-guidelines are highly recommended over IWC-guidelines for patients with potentially-curable and routinely FDG-avid lymphoma. In contrast, no additional value of IWC + PET was demonstrated in a small group of patients with incurable histological subtypes.

Hodgkin lymphoma: Response assessment by Revised International Workshop Criteria

Until recently, response assessment in patients with Hodgkin's lymphoma (HL) was primarily performed by computed tomography (CT). Based on CT, International Workshop Criteria (IWC) were developed and widely used. Fluorodeoxyglucose positron emission tomography (FDG-PET) has a higher sensitivity and specificity compared with that of CT, and Revised International Workshop Criteria (IWC + PET) were recently proposed, which combine both imaging techniques. We determined whether these integrated IWC + PET-criteria can more accurately predict outcome compared with IWC-criteria in 56 patients with HL. Of the original 56 patients, nine patients relapsed and 47 are still in remission after a median follow-up of 9 years. Based on IWC-criteria, 15 patients had a complete remission (CR) after chemotherapy, 20 had complete remission unconfirmed (CRu), 19 had partial remission (PR) and two had stable disease (SD). In comparison, by IWC + PET, 47 had CR, seven had PR and two had SD. For IWC, outcome was not significantly different in patients with CR/CRu compared to PR (P = 0.61), while for IWC + PET criteria, time-to-next-treatment was significantly shorter in patients with PR compared to CR (P = 0.01). Therefore, IWC + PET-guidelines provide a more accurate response classification compared with that of IWC-guidelines, and are the preferred method for response assessment in patients with Hodgkin's lymphoma.

Positron emission tomography in mantle cell lymphoma

Mantle cell lymphoma (MCL) is a rare but aggressive non-Hodgkin lymphoma subtype with a poor prognosis; most patients relapse despite initial response to therapy. Response was traditionally evaluated by computed tomography (CT), but the introduction of [(18)F]Fluorine-Deoxyglucose Positron Emission Tomography (PET) changed response assessment in aggressive lymphoma. However, the value of PET-evaluation in MCL has not been studied yet. Therefore, PET- and CT-findings were investigated in 37 patients with MCL (239 scans) and categorised following standardised response criteria for CT-evaluation (IWC-criteria), PET-evaluation (EORTC-criteria) and combined PET/CT-evaluation (IWC + PET-criteria). FDG-PET showed a high sensitivity for the detection of deposits of MCL and a higher FDG-uptake was shown in patients with the more aggressive blastoid-variant of MCL versus common MCL. However, routine use of PET for end-of-treatment response assessment in MCL cannot be recommended because CT- and PET-based designation systems had equivalent prognostic value. PET-based end-of-treatment response assessment only provided additional information over CT-based response assessment in a subpopulation of patients with highly FDG-avid MCL. PET allowed early detection of preclinical relapse during post-therapy surveillance, but the therapeutic consequences of such information are currently unclear.

Prospective comparative study of integrated positron emission tomography-computed tomography scan compared with remediastinoscopy in the assessment of residual mediastinal lymph node disease after induction chemotherapy for mediastinoscopy-proven stage IIIA-N2 Non-small-cell lung cancer: a Leuven Lung Cancer Group Study

PURPOSE

Mediastinal restaging after induction therapy for non-small-cell lung cancer remains a difficult and controversial issue. The goal of this prospective study was to compare the performance of integrated positron emission tomography (PET)--computed tomography (CT) and remediastinoscopy in the evaluation of mediastinal lymph node metastasis after induction chemotherapy.

PATIENTS AND METHODS

Thirty consecutive stage IIIA-N2 non-small-cell lung cancer patients surgically treated at our institution were entered onto this prospective study. N2 disease was proven by cervical mediastinoscopy, at which a mean number of 3.8 lymph node levels were biopsied. After completion of induction chemotherapy, the mediastinum was reassessed by integrated PET-CT and remediastinoscopy. All patients underwent thoracotomy with attempted complete resection and systematic nodal dissection.

RESULTS

PET-CT showed no evidence of nodal disease (N0) in 13 patients, Hilar nodal disease (N1) disease in three patients, and residual mediastinal disease (N2) in 14 patients. Remediastinoscopy was positive in only five patients. The preinduction involved lymph node level could be accurately re-evaluated in 18 patients. This was not the case in the other 12 because of extensive fibrosis and adhesions. In 17 patients, persistent N2 disease was found at thoracotomy. The sensitivity, specificity, and accuracy of PET-CT were 77%, 92%, and 83%, respectively. These parameters for remediastinoscopy were 29%, 100%, and 60%, respectively. Sensitivity (P < .0001) and accuracy (P = .012) were significantly better for PET-CT.

CONCLUSION

After a thorough staging mediastinoscopy, postinduction remediastinoscopy had a disappointing sensitivity because of adhesions and fibrosis. Integrated PET-CT yielded a better result than that obtained in previous studies with side-by-side PET and CT images.

Amyloidosis of the heart and respiratory system

Since the incidence of amyloidosis is increasing, the purpose of this article is to review the imaging features of intrathoracic amyloidosis. Amyloidosis forms a heterogeneous group of disorders characterised by the extracellular deposition of a homologous protein complex. The heart is the most commonly involved organ in the chest. Respiratory amyloidal deposition is much less common and may be generalised, when it occurs as a part of a systemic disease, or it may be restricted only to the respiratory system. Although, the abnormalities are considered non-specific, recent literature suggests-especially for cardiac amyloidosis-specific patterns of abnormalities.

Is there a role for FGD-PET in radiotherapy planning in esophageal carcinoma?

BACKGROUND AND PURPOSE

To determine the additional value of FDG-positron emission tomography (PET) to optimize delineation of the clinical target volume (CTV) in patients with advanced esophageal carcinoma.

METHODS AND MATERIALS

The imaging and radiotherapy data from 30 patients with an advanced esophageal carcinoma were analysed. The lymph node classification for esophageal cancer was modified and translated into anatomical volumes on computed tomography (CT). The so defined 14 different regions were scored individually for lymph node involvement on CT, endoscopic ultrasound (EUS) and FDG-PET. The influence of discordant findings between conventional and functional imaging on the decision as to what should be irradiated was assessed.

RESULTS

In 14 of the 30 patients (47%) discordances were found in detection of the pathological lymph nodes between CT/EUS and FDG-PET. In 8 patients, 9 lymph node regions were found with pathologic nodes on conventional imaging only. In three of these patients the influence of FDG-PET findings would have led to a decrease of the irradiated volume. In 6 patients, 8 lymph node regions were found with a normal CT/EUS and pathologic nodes on FDG-PET. In three of these patients (10%) the influence of the FDG-PET would have led to enlargement of the irradiated volume.

CONCLUSIONS

The chance of a false negative result on FGD-PET is not negligible; therefore, the irradiated volume should not be reduced based on a negative FDG-PET in a region with suspect nodes on other investigations. However, due to the high specificity of FDG-PET enlarging the irradiated volume based on a positive FDG-PET in a region without suspected lymph nodes on CT and/or EUS should be considered. This indicates a role for FDG-PET in radiotherapy planning for esophageal cancer.

Role of computed tomography in lung cancer staging

PURPOSE OF REVIEW

Computed tomography has always been an important imaging technique in lung cancer staging but, due to its well-known limitations, additional imaging and/or invasive tests are usually performed. Purpose of this review is to determine whether new developments in CT and in the other staging techniques have changed the role of CT.

RECENT FINDINGS

Despite important technical improvements and the availability of new CT applications, the recent literature confirms the limitations of CT in staging patients with NSCLC. Most attention was given however to other invasive and noninvasive staging techniques and their accuracy in comparison with CT. It was shown that FDG-PET is very useful in the preoperative patient with NSCLC and that it is, especially in N-staging, more accurate than CT. Also combining CT or FDG-PET with EUS-FNA biopsy seems to be a good approach in some indications. Finally, the first reports on the use of integrated PET-CT scanners in lung cancer staging were published and very promising results were shown.

SUMMARY

Computed tomography stays nevertheless the routine imaging procedure for staging patients with NSCLC although performing a PET scan in addition to this CT examination seems to be a good approach that can reduce but certainly not always avoid invasive staging procedures. Mediastinoscopy is still generally considered the standard of care when tissue needs to be obtained from suspicious nodes on FDG-PET and/or CT, although minimally invasive biopsy techniques could replace to a large extent this more invasive technique in the near future.

Mediastinal emphysema and small cell lung cancer (SCLC): a case-report

We present a case of a 59-year-old man with small cell lung cancer (SCLC) who developed heavy thoracic pain because of spontaneous mediastinal emphysema. Autopsy documented a mucosal lesion in the posterior tracheal wall with air leak towards the mediastinum. The occurrence of spontaneous mediastinal emphysema in patients with small cell lung cancer has rarely been described in the literature.

Additional Value of Whole-Body Fluorodeoxyglucose Positron Emission Tomography in the Detection of Distant Metastases of Non–Small-Cell Lung Cancer

The purpose of this work was to evaluate the additional value of whole-body positron emission tomography (WB-PET) in the distant staging of non-small-cell lung cancer (NSCLC). One hundred forty-four patients with NSCLC in whom conventional staging (CS) was negative or equivocal for metastases, and who underwent WB-PET as part of their initial work-up, were retrospectively analyzed. Conventional staging consisted of thoracic computed tomography (CT), upper abdominal ultrasound and/or CT, and bone scintigraphy or brain CT on indication. Final M stage was based on histology, additional imaging, or follow-up of = 18 months. An additional lesion suspect for metastasis was found on WB-PET in 11 patients. This was true positive in 7 (3 bone, 1 retroperitoneal lymph nodes, 1 lung, and 2 asymptomatic coexisting colorectal cancer) and false positive in 4 patients (3 bowel, 1 breast). Twenty-four lesions in 21 patients remained equivocal after CS. Whole- body PET correctly characterized 20 lesions in 18 patients as true positive (n = 1) or true negative (n = 19). Whole-body PET was false positive in one patient (adrenal adenoma) and false negative in 2 patients (2 bone, 1 lung lesion). Despite negative results of modern CS and WB-PET, 16 of 86 patients (19%) who underwent a curative resection, experienced a systemic relapse. After thorough modern CS, WB-PET correctly detected additional distant malignant lesions in only 5% of the patients, while the combined staging strategy probably still misses micrometastatic disease in one fifth of the patients. The most important contribution of WB-PET was its ability to exclude malignancy in the majority of distant lesions with equivocal CS.