UK Lung Cancer RCT Pilot Screening Trial: baseline findings from the screening arm provide evidence for the potential implementation of lung cancer screening

Background

Lung cancer screening using low-dose CT (LDCT) was shown to reduce lung cancer mortality by 20% in the National Lung Screening Trial.

Methods

The pilot UK Lung Cancer Screening (UKLS) is a randomised controlled trial of LDCT screening for lung cancer versus usual care. A population-based questionnaire was used to identify high-risk individuals. CT screen-detected nodules were managed by a pre-specified protocol. Cost effectiveness was modelled with reference to the National Lung Cancer Screening Trial mortality reduction.

Results

247 354 individuals aged 50–75 years were approached; 30.7% expressed an interest, 8729 (11.5%) were eligible and 4055 were randomised, 2028 into the CT arm (1994 underwent a CT). Forty-two participants (2.1%) had confirmed lung cancer, 34 (1.7%) at baseline and 8 (0.4%) at the 12-month scan. 28/42 (66.7%) had stage I disease, 36/42 (85.7%) had stage I or II disease. 35/42 (83.3%) had surgical resection. 536 subjects had nodules greater than 50 mm³ or 5 mm diameter and 41/536 were found to have lung cancer. One further cancer was detected by follow-up of nodules between 15 and 50 mm³ at 12 months. The baseline estimate for the incremental cost-effectiveness ratio of once-only CT screening, under the UKLS protocol, was £8466 per quality adjusted life year gained (CI £5542 to £12 569).

Conclusions

The UKLS pilot trial demonstrated that it is possible to detect lung cancer at an early stage and deliver potentially curative treatment in over 80% of cases. Health economic analysis suggests that the intervention would be cost effective—this needs to be confirmed using data on observed lung cancer mortality reduction.

Trial registration

ISRCTN 78513845.

Chronic Aspergillosis of the Lungs: Unravelling the Terminology and Radiology

The propensity for Aspergillus spp. to cause lung disease has long been recognised but the satisfactory classification of these disorders is challenging. The problems caused by invasive disease in severely neutropenic patients, saprophytic infection of pre-existing fibrotic cavities and allergic reactions to Aspergillus are well documented. In contrast, a more chronic form of Aspergillus-related lung disease that has the potential to cause significant morbidity and mortality is under-reported. The symptoms of this form of Aspergillus infection may be non-specific and the radiologist may be the first to suspect a diagnosis of chronic pulmonary aspergillosis. The current review considers the classification conundrums in diseases caused by Aspergillus spp. and discusses the typical clinical and radiological profile of patients with chronic pulmonary aspergillosis.

KEY POINTS

• The classification of Aspergillus -related lung disease is mired in confusion. • The chronic form of Aspergillus infection is associated with significant morbidity and mortality. • Progressive consolidation and cavitation with intracavitary material is the radiological hallmark.

Optimal scoring of serial change on chest radiography in sarcoidosis

BACKGROUND

The optimal means of quantifying change on chest radiography in sarcoidosis is uncertain. In current guidelines, the role of serial measurement of carbon-monoxide diffusing capacity (DLco) remains undefined and the prevalence of discordance between serial chest radiographic change and pulmonary function tends is unknown.

OBJECTIVE

To identify and explore key uncertainties in the monitoring of sarcoidosis by serial pulmonary function tests and chest radiography.

DESIGN

354 patients with sarcoidosis and concurrent tests (chest radiography and PFTs within three months at baseline, two years and/or four years) were studied. Chest radiographs were assessed by two radiologists for changes in stage and disease extent. Radiographic change and pulmonary function trends were quantified and compared.

RESULTS

Change in radiographic extent of lung disease was always more frequent than change in stage (p < 0.0001) and there was poor agreement between change in stage and change in radiographic extent (Kw = 0.21 at two years; Kw = 0.23 at four years). Change in disease extent on chest radiography was linked to PFT trends on analysis of variance (p < 0.0005 for FEV1, FVC, DLco), whereas change in radiographic stage was not. Changes in gas transfer were often isolated or discordant with other serial data. Discordance between pulmonary function data and chest radiographic data was observed in 50% of cases.

CONCLUSIONS

Change in radiographic extent is more applicable to routine monitoring in sarcoidosis than change in radiographic stage. In future guidelines, the role of serial gas transfer estimation and reconciliation of divergent chest radiographic and functional trends might usefully be addressed.

Significance of connective tissue disease features in idiopathic interstitial pneumonia

In idiopathic interstitial pneumonia (IIP), the significance of connective tissue disease (CTD) features in the absence of a specific CTD diagnosis remains unclear. We studied the clinical and prognostic utility of a diagnosis of undifferentiated CTD (UCTD) in patients with biopsy-proven IIP. IIP patients undergoing surgical lung biopsy (1979-2005) were studied (nonspecific interstitial pneumonia (NSIP), n = 45; idiopathic pulmonary fibrosis, n = 56). UCTD was considered present when serum autoantibodies were present and symptoms or signs suggested CTD. The relationship between UCTD and NSIP histology was evaluated. A clinical algorithm that best predicted NSIP histology was constructed using a priori variables. The prognostic utility of UCTD, and of this algorithm, was evaluated. UCTD was present in 14 (31%) NSIP and seven (13%) IPF patients. UCTD was not associated with a survival benefit. The algorithm predictive of NSIP (OR 10.4, 95% CI 3.21-33.67; p<0.0001) consisted of the absence of typical high-resolution computed tomography (HRCT) features for IPF and 1) a compatible demographic profile (females aged <50 yrs) or 2) Raynaud's phenomenon. In patients with an HRCT scan not typical for IPF, this algorithm predicted improved survival (hazard ratio 0.35, 95% CI 0.14-0.85; p = 0.02) independent of IIP severity. UCTD is associated with NSIP histology. However, the diagnostic and prognostic significance of UCTD in IIP patients remains unclear.

Increased epithelial permeability in pulmonary fibrosis in relation to disease progression

Epithelial injury contributes to pathogenesis in idiopathic pulmonary fibrosis (IPF) but its role in the interstitial lung disease (ILD) of systemic sclerosis (SSc) is uncertain. We quantified the prognostic significance of inhaled technetium-99m ((99m)Tc)-labelled diethylene triamine pentacetate (DTPA) pulmonary clearance, a marker of the extent of epithelial injury, in both diseases. Baseline (99m)Tc-DTPA pulmonary clearance was evaluated retrospectively in patients with SSc-ILD (n = 168) and IPF (n = 97) against mortality and disease progression. In SSc-ILD, the rapidity of total clearance (hazard ratio (HR) 1.02, 95% CI 1.01-1.03; p = 0.001) and the presence of abnormally rapid clearance (HR 2.10; 95% CI 1.25-3.53; p = 0.005) predicted a shorter time to forced vital capcity (FVC) decline, independent of disease severity. These associations were robust in both mild and severe disease. By contrast, in IPF, delayed clearance of the slow component, an expected consequence of honeycomb change, was an independent predictor of a shorter time to FVC decline (HR 1.01, 95% CI 1.00-1.02; p<0.01). Epithelial injury should be incorporated in pathogenetic models in SSc-ILD. By contrast, outcome is not linked to the overall extent of epithelial injury in IPF, apart from abnormalities ascribable to honeycombing, suggesting that core pathogenetic events may be more spatially focal in that disease.

High-resolution CT of complications of idiopathic fibrotic lung disease

Idiopathic pulmonary fibrosis (IPF) has a more variable clinical course than has been traditionally recognised. Many patients will remain stable over time while others experience relatively rapid deterioration. The prognosis and clinical course of patients with other fibrosing lung diseases is also variable. A number of conditions may complicate the clinical course of the idiopathic fibrosing lung diseases, which results in morbidity and mortality, but also represents potentially treatable causes of worsening symptoms. Infection and malignancy have a long-recognised association with IPF while other conditions, particularly pulmonary hypertension and acute exacerbation of IPF, are being increasingly recognised in this patient population. Many of these patients have serial high-resolution CT (HRCT) examinations that may demonstrate one or more of these supervening conditions. In this article we review the more common conditions that may complicate the course of idiopathic fibrosing lung disease with an emphasis on the HRCT appearance, which the reporting radiologist should be aware of.

UK Lung Screen (UKLS) nodule management protocol: modelling of a single screen randomised controlled trial of low-dose CT screening for lung cancer

The UK Lung Screen (UKLS) is a randomised controlled trial of the use of low-dose multidetector CT for lung cancer screening. It completed the Health Technology Appraisal (HTA)-funded feasibility stage in October 2009 and the pilot UKLS will be initiated in early 2011. The pilot will randomise 4000 subjects to either low-dose CT screening or no screening. The full study, due to start in September 2012, if progression criteria are met, will randomise a further 28 000 subjects from seven centres in the UK. Subjects will be selected if they have sufficient risk of developing lung cancer according to the Liverpool Lung Project risk model. The UKLS employs the ‘Wald Single Screen Design’, which was modelled in the UKLS feasibility study. This paper describes the modelling of nodule management in UKLS by using volumetric analysis with a single initial screen design and follow-up period of 10 years. This modelling has resulted in the development and adoption of the UKLS care pathway, which will be implemented in the planned CT screening trial in the UK.

Atelectasis and survival after bronchoscopic lung volume reduction for COPD

Bronchoscopic therapies to reduce lung volumes in chronic obstructive pulmonary disease are intended to avoid the risks associated with lung volume reduction surgery (LVRS) or to be used in patient groups in whom LVRS is not appropriate. Bronchoscopic lung volume reduction (BLVR) using endobronchial valves to target unilateral lobar occlusion can improve lung function and exercise capacity in patients with emphysema. The benefit is most pronounced in, though not confined to, patients where lobar atelectasis has occurred. Few data exist on their long-term outcome. 19 patients (16 males; mean±sd forced expiratory volume in 1 s 28.4±11.9% predicted) underwent BLVR between July 2002 and February 2004. Radiological atelectasis was observed in five patients. Survival data was available for all patients up to February 2010. None of the patients in whom atelectasis occurred died during follow-up, whereas eight out of 14 in the nonatelectasis group died (Chi-squared p=0.026). There was no significant difference between the groups at baseline in lung function, quality of life, exacerbation rate, exercise capacity (shuttle walk test or cycle ergometry) or computed tomography appearances, although body mass index was significantly higher in the atelectasis group (21.6±2.9 versus 28.4±2.9 kg·m(-2); p<0.001). The data in the present study suggest that atelectasis following BLVR is associated with a survival benefit that is not explained by baseline differences.

Marginal decline in forced vital capacity is associated with a poor outcome in idiopathic pulmonary fibrosis

In therapeutic studies in idiopathic pulmonary fibrosis (IPF), the low prevalence of significant change in pulmonary functional tests (PFTs) has been a major constraint. The prognostic value of "marginal" changes in PFTs in IPF and fibrotic non-specific interstitial pneumonia (NSIP) was evaluated. In patients with biopsy-proven IPF (n = 84) and NSIP (n = 72), forced vital capacity (FVC) and diffusing capacity of the lung for carbon monoxide (D( L,CO)) trends at 6 months were categorised as "significant" (FVC >10%; D(L,CO) >15%) or "marginal" (FVC 5-10%; D(L,CO) 7.5-15%). Proportional hazards analysis and time-dependent receiver operating characteristic methodology were used to examine PFT trends against mortality. In IPF, reductions in FVC were significant in 22 cases (26%) and marginal in 19 cases (23%). Mortality was higher in patients with a significant decline in FVC (hazard ratio (HR) 2.80, 95% CI 1.54-5.06; p<0.001) and those with a marginal decline in FVC (HR 2.31, 95% CI 1.19-4.50; p = 0.01) than in those with stable disease. Progression-free survival was lower when the decline in FVC was marginal than in stable disease (HR 2.34, 95% CI 1.19-4.60; p = 0.01). Marginal changes in D(L,CO) in IPF and marginal changes in FVC and D (L,CO) in fibrotic NSIP did not provide useful prognostic information. Marginal change in FVC in IPF denotes a poor outcome. These findings are applicable to clinical practice and to the selection of patients with more progressive disease for therapeutic studies.

CT lung cancer screening in the UK

Lung cancer is the most common cause of cancer-related death in the UK. Despite aggressive primary prevention measures and improved medical care, the 5-year survival rate is less than 10% for patients in the UK who present with symptoms. The possibility of CT screening for lung cancer provides some hope of reducing mortality. However, the case for screening remains unproven. This article explores the issues surrounding lung cancer screening in the context of historical studies, trials in progress and tentative plans for a UK CT lung cancer screening trial.

Incidentally detected small pulmonary nodules on CT

The widespread use of multidetector computed tomography for imaging of the chest has lead to a significant increase in the number of incidentally detected pulmonary nodules. The significance of these nodules is often uncertain and further investigations may be required. This article will review the spectrum of imaging appearances of small pulmonary nodules, and highlight the few features that allow confident characterization of a nodule as benign or malignant; current guidelines for the management of incidentally detected nodules will also be discussed.

Use of intravenous cyclophosphamide in known or suspected, advanced non-specific interstitial pneumonia

BACKGROUND

In severe, progressive interstitial lung disease (ILD), specific diagnosis is often difficult, and treatment therefore empirical. An effective, rapidly acting, well-tolerated therapy is desirable. This study reviews the tolerability and efficacy of i.v. cyclophosphamide in known or suspected non-specific interstitial pneumonia (NSIP) following the introduction of an i.v. cyclophosphamide protocol.

METHODS

Records of 54 patients with biopsy-proven (n = 7) or suspected NSIP, based on clinico-radiological consensus (n = 47), receiving i.v. cyclophosphamide over 2004-6 were reviewed (excluding systemic sclerosis). Lung-function trends over six months were evaluated, and comparative analysis of paired pulmonary-function before and after the start of therapy was performed.

RESULTS

IV cyclophosphamide was well tolerated, with two withdrawals from therapy, and four deaths, not directly related to treatment. IV cyclophosphamide was associated with disease stability at six-months. Despite having severe, progressive disease, patients receiving i.v. cyclophosphamide had stable lung function at six months. A greater therapeutic response was associated with coexistent HRCT abnormalities indicative of organizing pneumonia. In 22 patients with paired pulmonary-function tests, pulmonary function trends were significantly improved (p = 0.03) and change in DLco differed significantly (p < 0.0001), following cyclophosphamide treatment.

CONCLUSION

In the empirical treatment of advanced, rapidly progressive known or suspected NSIP, i.v. cyclophosphamide is a well tolerated, rapidly acting immunosuppressant, associated with improvement or stability in most cases.

Pulmonary vascular resistance predicts early mortality in patients with diffuse fibrotic lung disease and suspected pulmonary hypertension

BACKGROUND

Pulmonary hypertension (PH) is associated with a poor prognosis in diffuse lung disease (DLD). A study was undertaken to compare the prognostic significance of invasive and non-invasive parameters in patients with DLD and suspected PH.

METHODS

Hospital records of consecutive patients with DLD undergoing right heart catheterisation (RHC) were reviewed (n = 66). Mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR) and non-invasive variables were examined against early (within 12 months) and overall mortality. A priori thresholds were examined against early mortality. Relationships between mPAP, PVR and non-invasive markers were assessed.

RESULTS

Fifty patients had PH on RHC (mean (SD) mPAP 33.5 (11.8) mm Hg, PVR 5.9 (4.3) Wood units (WU)). Raised PVR was strongly associated with early mortality (odds ratio (OR) 1.30; 95% confidence interval (CI) 1.11 to 1.52; p = 0.001), with PVR > or = 6.23 WU being the optimal threshold after adjustment for age, gender, composite physiological index (CPI) and diagnosis of idiopathic pulmonary fibrosis (OR 11.09; 95% CI 2.54 to 48.36; p = 0.001). Early mortality was linked, albeit less strongly, to right ventricular dilation at echocardiography, but not to other non-invasive variables or mPAP. Overall mortality was most strongly associated with increasing CPI levels. Correlations between PVR and non-invasive variables were moderate (R(2) <0.32), improving little following construction of a multivariate index which did not itself predict mortality.

CONCLUSION

In severe DLD, early mortality is strongly linked to increased PVR but not to other RHC or non-invasive variables. These findings suggest that the threshold for RHC in severe DLD should be low, enabling prioritisation of aggressive treatment including lung transplantation.

Mortality in bronchiectasis: a long-term study assessing the factors influencing survival

There is little literature about the mortality associated with bronchiectasis. The aim of the present study was to investigate factors affecting mortality in patients with bronchiectasis. In total, 91 patients were examined for aetiology, pulmonary function tests, high-resolution computed tomography, sputum microbiology and quality of life scores and were then followed over 13 yrs. Overall, 29.7% of the patients died. On multivariate analysis, age, St George's Respiratory Questionnaire activity score, Pseudomonas aeruginosa infection, total lung capacity (TLC), residual volume/TLC and the transfer factor coefficient were all independently associated with mortality. In patients with moderate to severe bronchiectasis, mortality is associated with a degree of restrictive and obstructive disease, poor gas transfer and chronic pseudomonas infection. These features should guide future research into disease progression, and identify those patients needing intensive treatment.

Computed tomography and cystic fibrosis: promises and problems

Computed tomography (CT) has two potential roles in the evaluation of patients with cystic fibrosis (CF) lung disease: as a diagnostic test primarily for the detection of supervening complications and as a monitoring tool in clinical research. Interest in the latter role has gained momentum in the last 5 years because of two factors: (1) therapeutic options for CF lung disease are developing rapidly, hence the need for an outcome measure that can be applied in clinical intervention trials; and (2) it has become clear that traditional outcome measures such as pulmonary function tests are relatively insensitive to the early structural damage that occurs in CF. Several recent studies have shown that CT can be used as a potential surrogate outcome measure, although its suitability for this specific role is controversial and still under investigation. This review summarises current concepts relating to the research applications of CT in CF, with particular emphasis on the evidence supporting the use of CT as a surrogate outcome measure in clinical trials.

PET/CT in non-small cell lung cancer staging—promises and problems

Integrated positron emission tomography/computed tomography (PET/CT) has many advantages over solitary PET and CT, which has led it to become an increasingly established imaging technique in the management of many cancers. This article will review the evidence for the role of (18)F-fluorodeoxyglucose PET/CT in non-small cell lung cancer staging, examining its strengths, weaknesses and cost-effectiveness.

Interstitial lung disease?the new synergy between radiology and pathology

In the last 30 years, high-resolution computed tomography (HRCT) has been the major advance in diagnosis of diffuse parenchymal lung disease (DPLD). We review the diagnostic accuracy of HRCT and discuss how the gold standard in diagnosis of DPLD has shifted from histopathological diagnosis in isolation to a multidisciplinary approach. This latter process is now accepted as providing the highest levels of diagnostic accuracy in patients with DPLD and lung biopsy is primarily reserved for cases with atypical clinical or radiological presentations.

Thin-section CT of the lungs: Eye-tracking analysis of the visual approach to reading tiled and stacked display formats

OBJECTIVE

To use eye-tracking analysis to identify the differences in approach to and efficiency of reading thin-section CT of the lungs presented tiled and stacked soft-copy displays.

MATERIALS AND METHODS

Four chest radiologists read 16 thin-section CT examinations displayed in either a tiled (four images at once) or stacked (full screen cine) format. Eye-movements were recorded and analysed in terms of movement type; saccade distance (classified by the calculated range of useful peripheral vision), number of fixations, duration and direction of gaze-comparison of the areas of the images viewed.

RESULTS

Cases presented in stacked format were read quicker than when presented in tiled format with a greater fixation frequency (5 fixations versus 4.5 fixations points per 100 data points; p<0.001) and a greater proportion of short saccades (97% versus 94%; p<0.005). The consistency with which the observers viewed equivalent areas of the scan images in different cases was greater when viewing in stacked format (mean kappa 0.45 versus 0.36; p<0.05) suggesting a more systematic approach to reading.

CONCLUSION

Eye-tracking data demonstrates why thin-section CT examinations of the lungs are read more efficiently when displayed in a stack as opposed to a tiled format.

Computed tomography and pulmonary function abnormalities in sickle cell disease

The aim of this study was to determine whether patients with sickle cell disease (SCD) in steady state had pulmonary abnormalities seen on high-resolution computed tomography (HRCT) and whether any abnormalities correlated with contemporaneously diagnosed lung function abnormalities. A subsidiary question was whether the results of a noninvasive measure of haemolysis (end-tidal carbon monoxide (ETCO) levels) correlated with pulmonary function abnormalities. Thirty three patients with SCD, median (range) age 36 yrs (17-67 yrs) were examined. The degree of lobar volume loss and ground-glass opacification and prominence of central vessels on HRCT were quantitatively assessed. Pulmonary function was assessed by measurements of lung volumes, spirometry, gas transfer and oxygen saturation. ETCO levels were measured using an end-tidal CO monitor. Forced expiratory volume in one second (FEV1), forced vital capacity and total lung capacity significantly correlated with HRCT findings, particularly lobar volume loss. ETCO levels significantly negatively correlated with FEV1, vital capacity measured using a plethysmograph, specific airway conductance and arterial oxygen saturation measured by pulse oxymetry. In conclusion, the present results suggest that high-resolution computed tomography noninvasive assessment of haemolysis might be useful to identify sickle cell disease patients with respiratory function impairment.

Pulmonary involvement by Niemann-Pick disease. A report of six cases

AIMS

Although pulmonary involvement is a known cause of morbidity in Niemann-Pick disease, histological features in the lung are not well characterized. The purpose of this study is to document the histological features seen in pulmonary involvement by types B and C Niemann-Pick disease and to correlate them with clinical and imaging data.

METHODS AND RESULTS

Surgical lung biopsies from six patients (four with type B and two with type C disease) were reviewed and all showed diffuse endogenous lipid pneumonia, with lesser involvement of the interstitium by fibrosis and foamy macrophage accumulation. In type B disease only, there was also fine cytoplasmic vacuolation within the cytoplasm of ciliated epithelial cells. Neither disease showed foamy changes within pneumocytes. One patient had a bronchial cast removed on whole lung lavage. Electron microscopy showed abnormal lamellar inclusions within lysosomes of affected cells in type B disease. In patients with type C disease, biopsies were undertaken as part of investigations into acute respiratory failure in the context of multiorgan systemic presentation. Three patients with type B disease had clinical disease limited to the lung, all adults (mean age of 40 years) with unexplained diffuse parenchymal lung disease and mainly ground-glass shadowing on high-resolution computed tomography.

CONCLUSIONS

Niemann-Pick disease should be considered for any patient with unexplained diffuse endogenous lipid pneumonia, even when disease is limited to the lungs and presentation is during adulthood.

Can HRCT be used as a marker of airway remodelling in children with difficult asthma?

Background

Whole airway wall thickening on high resolution computed tomography (HRCT) is reported to parallel thickening of the bronchial epithelial reticular basement membrane (RBM) in adult asthmatics. A similar relationship in children with difficult asthma (DA), in whom RBM thickening is a known feature, may allow the use of HRCT as a non-invasive marker of airway remodelling. We evaluated this relationship in children with DA.

Methods

27 children (median age 10.5 [range 4.1–16.7] years) with DA, underwent endobronchial biopsy from the right lower lobe and HRCT less than 4 months apart. HRCTs were assessed for bronchial wall thickening (BWT) of the right lower lobe using semi-quantitative and quantitative scoring techniques. The semi-quantitative score (grade 0–4) was an overall assessment of BWT of all clearly identifiable airways in HRCT scans. The quantitative score (BWT %; defined as [airway outer diameter – airway lumen diameter]/airway outer diameter ×100) was the average score of all airways visible and calculated using electronic endpoint callipers. RBM thickness in endobronchial biopsies was measured using image analysis. 23/27 subjects performed spirometry and the relationships between RBM thickness and BWT with airflow obstruction evaluated.

Results

Median RBM thickness in endobronchial biopsies was 6.7(range 4.6 – 10.0) μm. Median qualitative score for BWT of the right lower lobe was 1(range 0 – 1.5) and quantitative score was 54.3 (range 48.2 – 65.6)%. There was no relationship between RBM thickness and BWT in the right lower lobe using either scoring technique. No relationship was found between FEV₁ and BWT or RBM thickness.

Conclusion

Although a relationship between RBM thickness and BWT on HRCT has been found in adults with asthma, this relationship does not appear to hold true in children with DA.

High-resolution computed tomography of the lungs: the borderlands of normality

High-resolution computed tomography (HRCT) is now widely used in the assessment of airways and diffuse lung disease. Considerable literature on pathologic correlation has increased the understanding of the signs of disease seen on HRCT. However, neither the significance of subtle individual signs nor the spectrum of HRCT appearances in healthy lungs is well documented. HRCT signs that cause diagnostic uncertainty and the spectrum of findings that exist between definite normality and definite abnormality are discussed.

Desquamative interstitial pneumonia, respiratory bronchiolitis and their relationship to smoking

AIMS

Respiratory bronchiolitis (RB) and desquamative interstitial pneumonia (DIP) are closely associated histological patterns of interstitial pneumonia, although there are no studies on the extent of individual histological parameters. Furthermore, the term smoking related-interstitial lung disease (SR-ILD) has been proposed as a term to encompass patients with both these histological patterns who give a history of smoking, though it is not well defined how this term relates to historical cases of DIP. The aim of this study was to compare histological parameters in cases of DIP and RB and then to review in detail clinical, imaging and histological data for DIP in relation to a history of smoking.

METHODS AND RESULTS

Forty-nine cases were reviewed, 24 with RB and 25 with DIP; five cases of DIP were re-classified as RB on review due to bronchocentricity of the infiltrate. There was a significantly greater extent of interstitial fibrosis (P = 0.02), lymphoid follicles (P < 0.001) and eosinophilic infiltration (P < 0.0001) in patients with DIP compared with RB. In addition, the extents of these three parameters were significantly interrelated. Patients with DIP had a lower incidence of smoking (60%) when compared with patients with RB-ILD (93%) (P < 0.005). Further analysis of smokers versus never-smokers with DIP showed no difference in histological parameters, extent of haemosiderin deposition or the number of CD1a+ macrophages between the two groups, nor were there any differences in clinical data to suggest other aetiologies. Follow-up high-resolution computed tomography data from patients with DIP suggested that a pattern of fibrotic non-specific interstitial pneumonia (NSIP) may develop in the long term in both smokers and never-smokers.

CONCLUSION

There are significant differences in the extent of interstitial fibrosis, lymphoid follicles and eosinophilic infiltration between DIP and RB, as well as a much lower incidence of smoking in patients with DIP. Whether the lower reported incidence of smoking in DIP reflects referral bias or conservatism in giving a history of smoking remains uncertain, as neither histological parameters nor clinical data indicate a difference between smokers and never-smokers with DIP. Nevertheless, some cases of DIP are likely to remain idiopathic and unrelated to RB, though still have a good prognosis. Furthermore, they may evolve into a pattern resembling fibrotic NSIP. Therefore, whilst SR-ILD is appropriate in the correct clinical setting, the distinction between the histological patterns of RB and DIP remains appropriate.

Variations in histological patterns of interstitial pneumonia between connective tissue disorders and their relationship to prognosis

AIMS AND METHODS

Pulmonary parenchymal disease is common in patients with connective tissue disorders (CTDs). However, most reports precede recognition of non-specific interstitial pneumonia (NSIP). We have therefore reviewed 54 lung biopsies from 37 patients with polymyositis/dermatomyositis (PM/DM) (n = 13), Sjögren's syndrome (n = 5), rheumatoid arthritis (n = 17) and systemic lupus erythematosus (SLE) (n = 2) to assess the overall and relative frequencies of patterns of interstitial pneumonia and their impact on prognosis.

RESULTS AND CONCLUSIONS

NSIP was the most common pattern with an overall biopsy prevalence of 39% and patient prevalence of 41%. There was variation in prevalence between individual CTDs, with PM/DM commonly showing organizing pneumonia (n = 5), rheumatoid arthritis showing follicular bronchiolitis (n = 6) and Sjögren's syndrome showing chronic bronchiolitis (n = 4). These patterns presented either separately or in association with NSIP, occasionally with different patterns in biopsies from separate lobes. Only four patients showed a pattern of usual interstitial pneumonia (UIP): two with rheumatoid arthritis and one each with PM/DM and SLE. Overall mortality was 24%, the most frequently associated pattern being fibrotic NSIP (n = 5). In nine cases, pulmonary presentation preceded the systemic manifestation of the CTDs. When patients with CTDs present with chronic interstitial lung disease, the most common pattern is NSIP, although there is variation in pattern prevalence between individual disorders and patterns of interstitial pneumonia frequently overlap. These data suggest a different biology for intestitial pneumonias in CTDs when compared with the idiopathic interstitial pneumonias where UIP is the most common pattern. Mortality is similar to that seen in idiopathic NSIP and, coupled with pulmonary presentation occurring prior to the systemic manifestation of disease, this may have a bearing on the origin of some cases of putative idiopathic NSIP.

HRCT lung abnormalities are not a surrogate for exercise limitation in bronchiectasis

In paediatric bronchiectasis, there has been limited work on the relationship between disease severity as assessed by exercise limitation and high resolution computed tomography (HRCT). An observational study was performed on 36 children who completed a questionnaire, physical examination, spirometry and sputum analysis, followed by a low dose of radiation protocol chest computed tomography (CT) scan and cycle ergometry incremental exercise test. A modified Bhalla score was used to score the HRCT abnormalities. The exercise variables used to assess functional status were heart rate, oxygen consumption, oxygen saturations and time of exercise. The results were compared with established normal paediatric values. The median (range) age of the children was 13 yrs (10.6-17.1). Age, sex, height, weight or pubertal status were equally distributed between the children with cystic fibrosis (CF) or non-CF bronchiectasis. The children with non-CF bronchiectasis had a lower median forced expiratory volume in one second % predicted than the children with CF (69% versus 76%, respectively). The distribution of lung disease differed between the two groups. The children with CF bronchiectasis had predominantly right upper lobe disease, and scored higher for the presence and extent of bronchiectasis. Otherwise, there was no statistical difference in the overall CT score or the individual CT parameters between the groups. There was evidence of exercise limitation in both CF and non-CF bronchiectasis compared to normal children. No consistent relationships were identified between the lung function parameters, HRCT findings or exercise parameters in either disease group. In this study, high resolution computed tomography features were not found to be markers of exercise capacity. As spirometry, high resolution computed tomography features and exercise testing give different information in children with cystic fibrosis and non-cystic fibrosis bronchiectasis, the current authors suggest all three may be required for the comprehensive assessment of respiratory status.

Quantifying pulmonary perfusion in primary pulmonary hypertension using electron-beam computed tomography

Traditionally, a gravitational distribution of pulmonary perfusion has been described in normal subjects. How this may vary in patients with primary pulmonary hypertension (PPH), which is characterised by vascular obstruction due to intimal thickening, smooth muscle cell proliferation and episodes of thrombosis in small and medium sized pulmonary arteries, is unclear. In this study the potential of electron-beam computed tomography in quantifying the distribution of pulmonary perfusion in patients with PPH was investigated. Contrast-enhanced sections were obtained during inspiration in the supine position at baseline and during administration of the vasodilator adenosine in five healthy subjects and five patients with PPH. Under each experimental condition, regions of interest were placed along the nondependent-to-dependent axis and values for relative perfusion derived. In healthy individuals, a marked nondependent-to-dependent gradient in perfusion was observed. By contrast, in PPH, perfusion values were significantly lower and were uniform across the lung section, although the administration of adenosine resulted in increased perfusion in all regions of interest. Electron-beam computed tomography provides physiological and structural information about the pulmonary circulation in subjects with pulmonary vascular disease.

HRCT diagnosis of diffuse parenchymal lung disease: inter-observer variation

BACKGROUND

This study was designed to measure inter-observer variation between thoracic radiologists in the diagnosis of diffuse parenchymal lung disease (DPLD) using high resolution computed tomography (HRCT) and to identify areas of difficulty where expertise, in the form of national panels, would be of particular value.

METHODS

HRCT images of 131 patients with DPLD (from a tertiary referral hospital (n = 66) and regional teaching centres (n = 65)) were reviewed by 11 thoracic radiologists. Inter-observer variation for the first choice diagnosis was quantified using the unadjusted kappa coefficient of agreement. Observers stated differential diagnoses and assigned a percentage likelihood to each. A weighted kappa was calculated for the likelihood of each of the six most frequently diagnosed disease entities.

RESULTS

Observer agreement on the first choice diagnosis was moderate for the entire cohort (kappa = 0.48) and was higher for cases from regional centres (kappa = 0.60) than for cases from the tertiary referral centre (kappa = 0.34). 62% of cases from regional teaching centres were diagnosed with high confidence and good observer agreement (kappa = 0.77). Non-specific interstitial pneumonia (NSIP) was in the differential diagnosis in most disagreements (55%). Weighted kappa values quantifying the likelihood of specific diseases were moderate to good (mean 0.57, range 0.49-0.70).

CONCLUSION

There is good agreement between thoracic radiologists for the HRCT diagnosis of DPLD encountered in regional teaching centres. However, cases diagnosed with low confidence, particularly where NSIP is considered as a differential diagnosis, may benefit from the expertise of a reference panel.

Pulmonary fibrosis and lung cancer: risk and benefit analysis of pulmonary resection

OBJECTIVE

Pulmonary fibrosis is associated with an increased risk of lung cancer and outcome of surgical resection in this setting is unknown.

METHODS

We studied 22 patients (24 operations) with pulmonary fibrosis and non-small cell lung cancer treated between 1991 and 2000 (study group) and compared outcome with 951 other patients (964 operations) treated for non-small cell lung cancer over the same period (control patients).

RESULTS

The two groups did not differ significantly in age (68 vs 65 years), smoking history (86% vs 95% smokers), forced expiratory volume in 1 second (2.5 L/min vs 2.3 L/min) or forced vital capacity (3.2 L vs 3.7 L), but patients with pulmonary fibrosis were more likely to be male (72% vs 58%, P <.05). The operative mortality was higher in patients with pulmonary fibrosis than in control patients (17% vs 3.1%, P <.01) and there was a higher procedure-specific mortality in pulmonary fibrosis for pneumonectomy (33% vs 5.1%, P <.01) and lobectomy (12% vs 2.6%, P <.01). Patients with pulmonary fibrosis had a higher incidence of postoperative lung injury, (21% vs 3.7%, P <.01) and a longer mean hospital stay (17 vs 9 days, P <.05). In patients with pulmonary fibrosis, the actuarial 3-year survival was 54%. There were 11 deaths in the study group, 4 postoperatively (all acute respiratory distress syndrome) and 7 late deaths (metastatic disease, n = 2; progressive pulmonary fibrosis, n = 5). Median follow-up (to death or last review) was 13 months (range, 0-120 months). Five patients developed postoperative acute respiratory distress syndrome and in 4 of these patients this proved to be fatal. Postoperative acute respiratory distress syndrome was associated with lower preoperative total lung carbon monoxide diffusion capacity (median, 58% vs 70%, P =.03) and lower preoperative carbon monoxide diffusion capacity corrected for alveolar volume (median, 48% vs 58%, P =.05) and a higher preoperative composite physiological index (median, 44 vs 33, P =.008). None of the preoperative lung function parameters or operative finding were predictors of late death.

CONCLUSION

Patients with pulmonary fibrosis undergoing pulmonary resection for non-small cell lung cancer have increased postoperative morbidity and mortality, but an important subgroup has a good long-term outcome. Postoperative acute respiratory distress syndrome is associated with low preoperative gas transfer and a high composite physiological index. Resection of non-small cell lung cancer is appropriate in pulmonary fibrosis, provided that the level of functional impairment is carefully factored into patient selection.

Pulmonary perfusion quantified by electron-beam computed tomography: effects of hypoxia and inhaled NO

Patients with acute lung injury may benefit from the manipulation of pulmonary blood flow using inhaled nitric oxide (iNO) to optimise ventilation/perfusion matching. Current techniques for studying changes in regional pulmonary perfusion are difficult to apply clinically. This study therefore investigated the potential of electron-beam computed tomography (EBCT) to quantify the effects of hypoxia and iNO on regional pulmonary perfusion in five healthy subjects. Contrast-enhanced sections were obtained sequentially under conditions of normoxia, hypoxia (fractional concentration of oxygen in inspired gas (FI,O2) 0.12) and hypoxia, with iNO (14.8 parts per million (ppm)) administered during inspiration in the supine position. Regions of interest were placed along the nondependent to dependent axis and values for relative perfusion derived. Under normoxic conditions a vertical gradient of perfusion existed, which became less apparent due to increased perfusion in nondependent regions after the induction of hypoxia (FI,O2 0.12). The addition of iNO (FI,O2 0.12 and NO 14.8 ppm) increased perfusion in all regions of the lung section, suggesting redistribution of pulmonary perfusion from other regions of the lung. Absolute values of perfusion were comparable to those documented with existing techniques. The use of a high spatial-resolution technique confirmed the presence of marked perfusion heterogeneity between anatomically close regions of lung.

Unusual sclerosing haemangiomas and sclerosing haemangioma-like lesions, and the value of TTF-1 in making the diagnosis

AIMS

Sclerosing haemangiomas typically comprise a mixture of four architectural patterns (papillary, sclerotic, solid and haemorrhagic) and two cell types, eosinophilic cuboidal epithelial lining cells and sheets of rounded cells with either eosinophilic or clear cytoplasm. In most instances, recognition of these architectural and cytological features provides sufficient evidence for diagnosis. This study presents and discusses the histogenesis of four cases where difficulties in diagnosis were encountered, and reports the value of the antibody TTF-1 in making the diagnosis.

METHODS AND RESULTS

Four cases with focal areas reminiscent of sclerosing haemangioma were reviewed and immunostained with an antibody panel including antibodies to TTF-1 and surfactant apoprotein A. Of these, one case was classified as sclerosing haemangioma combined with typical carcinoid, in which there was a mediastinal lymph node metastasis solely comprising the solid component of sclerosing haemangioma. The second was classified as an alveolar adenoma with sclerosing haemangioma-like areas. In the remaining two cases, diagnosis was confounded by presentation with predominantly cystic masses, the largest 70 mm in diameter. Immunohistochemically, TTF-1 was of greater value than surfactant apoprotein, in particular in identifying the solid component of sclerosing haemangioma when this was solely present.

CONCLUSION

Sclerosing haemangiomas should be considered in the differential diagnosis of cystic pulmonary masses. They may also present histologically as combined tumours and metastasize to mediastinal nodes, indicating an, albeit low, malignant potential. TTF-1 is a valuable antibody in identifying the presence of a sclerosing haemangioma when typical features are absent.

A comparison of serial computed tomography and functional change in bronchiectasis

In bronchiectasis the morphological determinants of (marginal) fluctuations in pulmonary function tests are uncertain. The aim of the present study was to evaluate serial computed tomography (CT) changes in relation to pulmonary function trends in patients with bronchiectasis. The relationships between pulmonary function indices and CT scans in 48 adult patients with bronchiectasis were evaluated at baseline and at follow-up, at a median interval of 28 months (range 6-74 months). Two independent observers semiquantitatively scored CT features of bronchial and small airways disease. At initial assessment, the severity of airflow obstruction was linked primarily to the extent of mosaic attenuation. However, serial changes in pulmonary function indices were only associated with serial changes in mucous plugging scores. Alterations in mucous plugging on serial CT were associated with changes in the severity of bronchiectasis and bronchial wall thickness. Greater severity of all three morphological abnormalities at baseline CT were predictive of significant declines in forced expiratory volume in one second, with severe bronchial wall thickness being the most adverse prognostic determinant. Variations in mucous plugging on computed tomography correlate with minor fluctuations in pulmonary function tests in bronchiectasis. However, the severity of bronchial wall thickness is the primary determinant of subsequent major functional decline.

Comparative appearances of non-tuberculous mycobacteria species: a CT study

Our objective was to characterise the CT features of the various species of non-tuberculous mycobacteria (NTM) and to identify differences, if any, between Mycobacterium avium intracellulare( MAI) and other species. Fifty-five patients, who were culture positive on at least two occasions for a single NTM species, were evaluated. All patients had CT scans performed within 6 months of NTM identification. The CT scans were assessed for the presence and severity of bronchiectasis, nodules, cavities, tree-in-bud pattern, consolidation and for evidence of pre-existing lung disease. Bronchiectasis was identified in most patients (52 of 55, 95%) and nodules were present in approximately half (29 of 55, 53%). Patients with MAI ( n=16) were found to have significantly higher bronchiectasis scores and higher prevalence of nodules than the other species (both p<0.01). Patients with M.kansasii ( n=9) and M.xenopi ( n=9) had cavities, tree-in-bud pattern, and pre-existing emphysema as the dominant CT features. Patients with M.chelonae and M.fortuitum were younger than the other groups and also had a high incidence of pre-existing lung disease. Patients with MAI infection have more severe bronchiectasis and more nodules on CT than the other NTM species. Morphological differences between the other species were identified but were less distinct.

Relationship between psychological well-being and lung health status in patients with bronchiectasis

Patients with bronchiectasis often complain of abnormal tiredness, difficulty in concentrating or low spirits. This study was carried out to examine levels of anxiety and depression in bronchiectasis and their relationship with other measures of lung health. One hundred and eleven patients with bronchiectasis determined by high-resolution computed tomography (CT) scan were studied using a range of physiological and psychological outcome measures. Patients completed anxiety and depression, health status (quality of life), fatigue and dypnoea questionnaires. Lung function was measured and exercise capacity was assessed using a shuttle walk test. Anxiety and depression scores formed a continuum. Moderate-severe anxiety was more frequent than equivalent levels of depression (17 vs 9% of patients). Anxiety and depression scores were associated with perceived health status (r=0.33 and 0.55). Neither anxiety nor depression was associated with the extent of bronchiectasis on CT scan. Depression was correlated with breathlessness and exercise performance (r=0.33 and 0.40), but anxiety was not. The correlation between depression and exercise performance was not simply due to the influence of somatic items in the depression questionnaire. We conclude that anxiety and depression are quite common in bronchiectasis in that 34% of patients had elevated scores for anxiety depression or both. The non-somatic components of depression were linked to dyspnoea and exercise performance, but anxiety was only related to perceived health. Therefore, treatment aimed at reducing symptoms and improving exercise capacity will not reduce levels of anxiety which need alternative therapy.