Bilateral Pleural Plaques Research Articles

ROUNDED ATELECTASIS: IS IT TRULY BENIGN?

SESSION TITLE: Wednesday Fellows Case Report Posters SESSION TYPE: Fellow Case Report Posters PRESENTED ON: 10/23/2019 09:45 AM - 10:45 AM INTRODUCTION: Rounded Atelactasis (RA) is a special type of peripheral lung collapse associated with focal pleural thickening, typically attributed to asbestos inhalation(1). RA is usually benign, and does not require any intervention, and is often misdiagnosed as a malignant lesion requiring patients to undergo unnecessary interventions. The co-existence of RA and lung cancer has been rarely reported in literature. Here, we present a 67-year-old male with RA, that was subsequently followed with a biopsy ten years later revealing adenocarcinoma. CASE PRESENTATION: 67-year-old male with minimal smoking history and medical history of hypertension, dyslipidemia presented outpatient as referral for an abnormal finding on his Cardiac CT for calcium scoring. Patient denied cough, shortness of breath, weight loss, hemoptysis, pleuritic chest pain and night sweats. All other review of system questions were answered in negative. Occupational history was positive for asbestos exposure but no family history of lung cancer. Physical exam was positive for mild decrease air entry on the left side. No clubbing, or lymphadenopathy was seen. Spirometry showed FVC and FEV1 of 59% and 54% of predicted respectively with FEV1/FVC ratio of 70. Previous CT chest from 2007 revealed bilateral pleural plaques and thickened pleura with 3 cm RA in left lower lobe. Repeat CT chest from 2010 showed stable 3 cm mass-like opacity likely representing RA with no evidence of parenchymal fibrosis. CT chest from 2018 showed interval increase in size of left lower lobe mass to 4.8 cm at the site of previous RA. Subsequent PET-CT showed increased uptake about the lesion, which was subsequently biopsied. Microscopically, tumor cells were positive for Napsin A and TTF-1, and no necrosis was appreciated in the biopsy sample. A histopathologic diagnosis of moderately differentiated adenocarcinoma was established. Patient has since been followed by our team and oncology as outpatient. DISCUSSION: RA results from in-folding of the lung in the presence of pleural fluid and fibrinous pleuritis(2). RA appears as a pleural-based mass-like lesion with a rounded shadow 2.5-5 cm in diameter lying along the lower lobe(3). CT typically shows a sharply marginated and homogeneous subpleural mass and volume loss in the affected lung, associated with adjacent pleural effusion or thickening, incurving vessels and bronchi, acute angles with pleura, and sharp lateral margins(4,5). CONCLUSIONS: Our patient possibly had stable RA initially that was later complicated by an underlying malignant process; a rare presentation with both entities co-existing independently of each other. This case educates us to be more aware of RA masking a potential underlying malignant process making it imperative to have recommended guidelines for follow-up of such lesions. Reference #1: Batra P, Brown K, Hayashi K, Mori M. Rounded atelectasis. Journal of Thorac Imaging. 1996;11(3): 187–197. Reference #2: Fraser RS, Muller NL, Colman N, Pare PD. Diagnosis of diseases of the chest, 4th ed. Philadelphia, PA: W. B. Saunders,1999 : 521–522. Reference #3: Schneider, H., Felson, B., & Gonzalez, L. (1980). Rounded atelectasis. American Journal of Roentgenology,134(2), 225-232. https://doi.org/10.2214/ajr.134.2.225 Doyle TC, Lawler GA. CT features of rounded atelectasis of the lung. AJR 1984; 143:225 –228 O'Donovan PB, Schenk M, Lim K, Obuchowski N, Stoller JK. Evaluation of the reliability of computed tomographic criteria used in the diagnosis of rounded atelectasis. J Thorac Imaging 1997; 12:54 –58. DISCLOSURES: No relevant relationships by Anas Al-khateeb, source=Web Response No relevant relationships by Sharath Bellary, source=Web Response No relevant relationships by Muqueet Kadri, source=Web Response No relevant relationships by Saraswathi Lakkasani, source=Web Response No relevant relationships by Richard Miller, source=Web Response No relevant relationships by Rutwik Patel, source=Web Response No relevant relationships by Hari Sharma, source=Web Response

On the diagnosis of malignant pleural mesothelioma: A necropsy-based study of 171 cases (1997-2016).

Malignant pleural mesothelioma (MPM) diagnosis is known to be difficult. We report on the diagnostic elements available in life in an MPM necropsy case series and describe the frequency of non-neoplastic asbestos-related diseases as biological exposure indices. We reviewed pathologic and clinical records of an unselected series of autopsies (1977-2016) in patients with MPM employed in the Monfalcone shipyards or living with shipyard workers. We assessed the consistency with autopsy results of diagnoses based on, respectively, radiologic, cytologic, and histologic findings, with and without immunophenotyping. Data on 171 cases were available: for 169, autopsy confirmed the MPM diagnosis. In life, 119 cases had histologic confirmation of diagnosis, whereas 7 were negative; all cases without immunophenotypization were autoptic MPMs. Cytology alone had been positive in 18 autoptic MPM cases, negative in 14. Radiologic imaging alone had been positive in another 16, negative in 11. In the 2 cases not confirmed at autopsy, MPM had been suspected by chest computed tomography only. Bilateral pleural plaques were found in 144 and histologic evidence of asbestosis in 62 cases. Autopsies confirmed 169/171 cases, including cases that would not be considered as certain based on diagnosis in life. Radiologic imaging, cytologic examination of pleural effusions, or both combined had low sensitivity but high positive predictive value: when they are positive, proceeding to thoracoscopy should be justified. MPM has been correctly diagnosed even without immunohistochemistry. The prevalence of pleural plaques and asbestosis was high due to severity of asbestos exposures in these cases.

Anthophyllite Asbestos: The Role of Fiber Width in Mesothelioma Induction Part 2: Further Epidemiological Studies of Occupational, Domestic and Environmental Exposure to Finnish Anthophyllite Asbestos

Although people in all sectors of the Finnish anthophyllite industry, including their families, have been heavily exposed to anthophyllite there is no evidence for even a single proven case of attributable mesothelioma. A few cases have been claimed but the evidence either, that they were mesotheliomas or that amphibole exposure was solely to anthophyllite is, in every case examined, insufficient. Even among the population who lived in Karelia in Central Finland who were exposed domestically or enviromentally to anthophyllite released during agricultural and various domestic activities and during transport from the mines, Finnish epidemiology found no risk of mesothelioma. There is also an absence of mesotheliomas reported in the earlier Finnish literature. This anomaly compared to the effects of exposure to other amphiboles is strong support for the role of fiber width in mesothelioma production. Anthophyllite, though, is not without clinical effect. As screening techniques improved it was discovered that of every person over the age of 65 years, one third living in Karelia had bilateral pleural plaques. The area was henceforth called the Endemic Pleural Plaque (EPP) zone. Radiographic analysis of the residents living in the district of Kuusjarvi led to suggestions that the cases resulted from asbestos blown from the Paakila facility via fiber drift as far away as 30 km. Later studies showed that ‘fiber drift’ was very unlikely to be a factor in the radiological findings thus observed.

Case-based discussion from North Tyneside General Hospital: somatostatin analogues in yellow nail syndrome associated with recurrent pleural effusions

Kristian Brooks (KB): A 77-year-old man presented to accident and emergency with a 1-month history of progressive breathlessness and reduced exercise tolerance. He had no chest pain, cough or wheeze,...

Pleural Plaque Related to Asbestos Mining in Taiwan

A 78-year-old woman complained of twisting-like pain in her left lower chest. During physical examination, friction rubbing was noted in both lungs. Chest radiography showed extensive bilateral pleural calcification. High-resolution computed tomography confirmed the presence of bilateral calcified pleural plaques. The patient had worked at a Japanese asbestos factory in Taiwan for 1 year when she was 16 years old. Her job involved picking out asbestos fibers from crushed asbestos minerals, but no protective equipment was used at that time. This is believed to be the first reported case of asbestos-related disease in Taiwan that resulted from asbestos mining. We also summarize the history of domestic asbestos mining, importation of asbestos, and trends in asbestos use in Taiwan.

Rare but Relevant Kidney Disorders

Rare but Relevant Kidney Disorders

Chest X-ray: what feature is of most concern?

![Graphic][1] The most obvious feature is probably the bilateral calcified pleural plaques, which are benign and consistent with previous asbestos … [1]: /embed/inline-graphic-1.gif

Circulating levels of interleukin-18 in asbestos-exposed workers

Occupational exposure to asbestos has been associated with the development of pulmonary diseases through a persistent inflammatory response initiated by reactive oxygen species and the subsequent release of proinflammatory mediators such as interleukin (IL)-1, IL-6 and tumour necrosis factor (TNF)-a. Recently, IL-18, a pleiotropic proinflammatory cytokine and potent inducer of gene expression and synthesis of INF-g, TNF-a and IL-1 in immunocompetent cells, has been described. IL-18 serum concentrations were measured in 20 asbestos-exposed workers and in a group of 20 healthy donors. The workers underwent physical examination, pulmonary function tests and high-resolution computed tomography (HRCT). IL-18 levels were assayed in peripheral blood using the immunoenzymatic method with a commercial kit. The pulmonary function tests revealed a restrictive ventilatory deficit in nine (45%) cases and an obstructive ventilatory deficit in five (25%). The remaining six (30%) workers exhibited normal spirometric values. HRCT findings were: bilateral pleural plaques in 8 (40%) workers and bilateral parenchymal fibrosis in 12 (60%), with mean scores of 2.559 / 1.89. The exposed workers displayed significantly higher IL-18 concentrations than controls and those with parenchymal fibrosis displayed significantly higher values than workers with pleural plaques (P=0.001). In subjects with parenchymal fibrosis, HRCT scores significantly correlated with serum levels of IL-18 (P=0.001). Although the mechanisms leading to IL-18 release in asbestosis are unknown, the present preliminary results underscore the potential role of this cytokine in the pathogenesis of pulmonary toxicity.

Ferruginous Bodies on Frozen Section

63-year-old man with a history of extensive asbestos exposure and cigarette smoking presented with shortness of breath. The asbestos exposure occurred while the patient was employed as a pipe insulator during the years 1959 to 1973. A computed tomographic scan of the lungs demonstrated bilateral pleural effusions, bilateral pleural plaques, and a 1.3-cm mass in the left lower lung lobe. A left lower lobectomy was performed, and sectioning of the lung demonstrated a 1.3-cm firm, tan-pink mass which was representatively frozen. Microscopically, the frozen section showed adenocarcinoma (Figure 1) associated with ferruginous bodies (Figure 1, arrow). Higher magnification of the ferruginous bodies demonstrated

Ferruginous bodies on frozen section.

63-year-old man with a history of extensive asbestos exposure and cigarette smoking presented with shortness of breath. The asbestos exposure occurred while the patient was employed as a pipe insulator during the years 1959 to 1973. A computed tomographic scan of the lungs demonstrated bilateral pleural effusions, bilateral pleural plaques, and a 1.3-cm mass in the left lower lung lobe. A left lower lobectomy was performed, and sectioning of the lung demonstrated a 1.3-cm firm, tan-pink mass which was representatively frozen. Microscopically, the frozen section showed adenocarcinoma (Figure 1) associated with ferruginous bodies (Figure 1, arrow). Higher magnification of the ferruginous bodies demonstrated

Computed tomography of asbestos-related pleural abnormalities.

To study the observer agreement in several asbestos-related pleural abnormalities and to define criteria to discriminate between pleural changes in workers with occupational disease, and those in controls. Pleural abnormalities in spiral computed tomography of 602 construction workers with asbestosis or bilateral pleural plaques and 49 controls were reviewed by three radiologists using structured forms. Intra- and inter-observer agreement (weighted kappa) was 0.4 or better with regard to the calcification, extent and thickness of pleural disease. These factors all correlated positively with the duration of asbestos exposure. There were significant differences in these pleural changes between the workers (mean extent per side 83 cm(2)) and controls (mean extent per side 40 cm(2)). Of the controls, 84% showed pleural lesions with an estimated extent of 10 cm(2) or more, bilateral in 64%. The extent of 45 cm(2) in pleural disease was the best value for discriminating between the controls and diseased workers, with a sensitivity of 82% and a specificity of 66%. The degree of pleural calcification, however, was the best discriminator between these groups, but quantitative methods are necessary for its use in the diagnostics of individuals. The extent, calcification and thickness were well-repeatable indicators of benign pleural pathology and thus their use in future classification systems in computed tomography is recommended. In our material, the extent of 45 cm(2) and the degree of calcification were helpful in discriminating between pleural changes in workers with occupational disease, and those in controls who also presented marked pleural pathology.

Asbestosis, pleural plaques and diffuse pleural thickening: three distinct benign responses to asbestos exposure.

The aim of this study was to investigate by computed tomography (CT) whether asbestosis, diffuse pleural thickening and/or pleural plaques are statistically associated. We also tried to find criteria to differentiate between diffuse and circumscribed pleural thickening. From 231 exposed workers, only those subjects whose radiograph showed neither bilateral calcified pleural plaques nor small pulmonary opacities higher than 1/1 grade according to the 1980 International Labour Office (ILO) Classification were considered. Scans were assessed for the presence of subpleural curvilinear lines, septal and intralobular lines, parenchymal bands, honeycombing, rounded atelectasis, pleural plaques and diffuse pleural thickening. CT scans revealed pleural and/or lung abnormalities in 99 workers. Pleural plaques were unilateral in one-third of cases with plaques. Diffuse pleural thickening, parenchymal bands and rounded atelectasis were unilateral in, respectively, 62 and 69 and 75% of cases with the abnormality. Septal and intralobular lines, and honeycombing were always bilateral. CT signs could be grouped into three patterns: 1) septal and intralobular lines, and honeycombing corresponding to pulmonary fibrosis; 2) pleural plaques corresponding to parietal pleural fibrosis; and 3) diffuse pleural thickening, rounded atelectasis and parenchymal bands corresponding to visceral pleural fibrosis. In these workers with a normal or near-normal radiograph, three groups of subjects with different responses were distinguished. Crow's feet and rounded atelectasis help to differentiate plaques from diffuse thickening.

Radiographic abnormalities among Finnish construction, shipyard and asbestos industry workers.

The prevalence of asbestos-related radiographic abnormalities was surveyed among Finnish construction, shipyard, and asbestos industry workers. The radiographic screening focused on active and retired workers who were under the age of 70 years and had been employed for at least 10 years in construction or for at least 1 year in shipyards or in the asbestos industry. In 1990-1992, 18,943 people participated in an X-ray examination of the lungs and an interview on work history and exposure. The criteria for a positive radiological finding were (i) small irregular lung opacities clearly consistent with interstitial pulmonary fibrosis (ILO 1/1 or higher), (ii) lung opacities indicating mild pulmonary fibrosis (ILO 1/0) with unilateral or bilateral pleural plaques, (iii) marked adhesions with or without thickening of the visceral pleura, or (iv) findings consistent with bilateral pleural plaques. Fulfilling the criteria were 4133 workers (22%) (22% from construction, 16% from shipyards, and 24% from the asbestos industry). The radiological findings included signs of pulmonary fibrosis (3%), changes in the visceral pleura (7%), bilateral plaques (17%), and unilateral plaques (10%). Occupational disease was diagnosed according to the Finnish insurance regulations for three-fourths of those referred for further examinations, 96% being abnormalities in the pleura and 4% being asbestosis. Exposure to asbestos dust has been common in ordinary construction work, and, consequently, radiographic abnormalities (mostly pleural) occur frequently among active and retired construction workers.

Asbestos exposure: A potential cause of retroperitoneal fibrosis

The etiology of retroperitoneal fibrosis is unknown in 70% of the cases. The aim of our study was to examine the possible association between occupational asbestos exposure and retroperitoneal fibrosis; only two cases have been reported in the literature. We gathered all the cases of retroperitoneal fibrosis diagnosed in the Tampere University Hospital between 1987 and 1995. We examined their hospital records to evaluate the possible etiology of the disease. We also sent a structured questionnaire to all living patients (10/13) to obtain information on their asbestos exposure. The chest radiographs of the patients were re-read to evaluate possible changes resulting from asbestos exposure. We found 13 cases of idiopathic retroperitoneal fibrosis. Seven patients (all male) had been exposed to asbestos in the past. The chest radiographs of the four most-exposed patients showed characteristic asbestos-related abnormalities, including bilateral pleural plaques, round atelectasis and small irregular lung opacities. In our study, we found that asbestos exposure and asbestos-induced changes in the lung and pleura were common among male retroperitoneal fibrosis patients. We suggest that occupational exposure to asbestos may be an important etiological factor for retroperitoneal fibrosis. Am. J. Ind. Med. 33:418–421, 1998. © 1998 Wiley-Liss, Inc.

Asbestos exposure: a potential cause of retroperitoneal fibrosis.

The etiology of retroperitoneal fibrosis is unknown in 70% of the cases. The aim of our study was to examine the possible association between occupational asbestos exposure and retroperitoneal fibrosis; only two cases have been reported in the literature. We gathered all the cases of retroperitoneal fibrosis diagnosed in the Tampere University Hospital between 1987 and 1995. We examined their hospital records to evaluate the possible etiology of the disease. We also sent a structured questionnaire to all living patients (10/13) to obtain information on their asbestos exposure. The chest radiographs of the patients were re-read to evaluate possible changes resulting from asbestos exposure. We found 13 cases of idiopathic retroperitoneal fibrosis. Seven patients (all male) had been exposed to asbestos in the past. The chest radiographs of the four most-exposed patients showed characteristic asbestos-related abnormalities, including bilateral pleural plaques, round atelectasis and small irregular lung opacities. In our study, we found that asbestos exposure and asbestos-induced changes in the lung and pleura were common among male retroperitoneal fibrosis patients. We suggest that occupational exposure to asbestos may be an important etiological factor for retroperitoneal fibrosis.

Screening for asbestos-induced diseases in Finland.

Screening for asbestos-induced diseases in Finland was carried out in 1990-1992 as a part of the Asbestos Program of the Finnish Institute of Occupational Health. The aim of the present study was to find the workers who had developed an asbestos-induced disease in certain occupations. Examination of active or retired workers included a personal interview on work history and asbestos exposure, and a chest X-ray. The target group for the screening comprised workers under 70 years of age who had worked at least for 10 years in construction, 1 year in a shipyard or in the manufacture of asbestos products. A preliminary questionnaire was sent to 54,409 workers, 18,943 of whom finally participated in the screening examination. The mean age of the workers was 53 years; 95% were employed in construction, 2% in shipyards, and 3% in the asbestos industry. The criteria for a positive screening result were (1) a radiographic finding clearly indicating lung fibrosis (at least ILO category 1/1), (2) a radiographic finding indicating mild lung fibrosis (ILO category 1/0) with unilateral or bilateral pleural plaques, (3) marked abnormalities of the visceral pleura (marked adhesions with or without pleural thickening), or (4) bilateral pleural plaques. The positive cases totalled 4,133 (22%) and were sent for further investigation. In addition to the screening, information on the presence of asbestos in the work environment, prevention of asbestos exposure, as well as on the health effects of asbestos exposure and smoking were given to the participating workers. The screening acted as a preliminary survey to prompt further national follow-up of asbestos-induced diseases among the workers who have been exposed to asbestos. This article presents the material, methods, and overall results of the screening.

Radiographic small lung opacities and pleural abnormalities in relation to smoking, urbanization status, and occupational asbestos exposure in Finland.

The role of smoking and an urban living environment in the etiology of radiographic pleural and pulmonary abnormalities was studied in a population sample that was representative of the Finnish adult population. A total of 7095 full-size chest radiographs were classified according to the International Labor Organization's 1980 classification of radiographs of pneumoconioses, with some modifications. The risk of bilateral pleural plaques was significantly higher among urban men (RR, 2.0) and women (RR, 3.8), even when adjusted for age and probability of occupational asbestos exposure and smoking. The risks of small lung opacities and abnormalities of the visceral pleura were not higher in urban areas. Risks of small lung opacities and thickening of the visceral pleura were positively associated with smoking, and the risk of small lung opacities was also higher among smokers than never-smokers in the population fraction with unlikely occupational asbestos exposure.

Environmental pleural plaques in an asbestos exposed population of northeast Corsica

The purpose of this study was to determine whether the inhabitants of villages environmentally exposed to asbestos, in northeast Corsica, had a higher incidence of pleural plaques. X-rays were obtained from subjects aged over 50 yrs, with no occupational exposure to asbestos or history of pleural disease, in one village exposed to asbestos, Murato, and a nonexposed, control village, Vezzani. In addition, the mineral content of the air and parietal pleura of animals in the exposed zone was studied, using transmission electron microscopy. The incidence of bilateral pleural plaques in the exposed population was 41%, as compared to 7.5% in the nonexposed population (p < 0.00001). The levels of airborne tremolite were higher in Murato (6-72 ng.m-3) than in Vezzani (< 1 ng.m-3), but chrysotile levels were similar. Significant numbers of chrysotile and tremolite fibres were identified in the parietal pleura of animals from the exposed village. This study confirms the well-known correlation between bilateral pleural plaques and environmental exposure to low levels of asbestos.

Asbestos induced pericardial effusion and constrictive pericarditis.

The number of disorders attributable to asbestos exposure has increased gradually over the years. The latest to be recorded is pericardial effusion and constrictive pericarditis, and three cases are reported here. A man with bilateral pleural thickening and plaques developed acute pericarditis and an effusion and was treated by pericardiectomy. Two men died from constrictive pericarditis associated with bilateral pleural effusions and diffusion pleural thickening. The pericardium showed nonspecific fibrous thickening. All had been occupationally exposed to asbestos. In the fatal cases the lungs contained amphibole fibres, in keeping with a modest degree of occupational exposure. Asbestos produces progressive fibrosis of the pericardium that is similar to diffuse pleural thickening and may be fatal. Both conditions may develop after relatively short or light exposure.

Minimal pathologic changes of the lung and asbestos exposure

A group of 199 autopsy subjects was investigated for minimal pathologic pulmonary changes possibly resulting from asbestos exposure. According to the standards proposed by the Pneumoconiosis Committee of the College of American Pathologists, features consistent with asbestosis grade 1 (AG1) include findings of bilateral pleural plaques, high concentrations of asbestos bodies (ABs) in digested lung tissue, and a history of occupational risk. Similar changes without evidence of ABs on histologic section and referred to as small airway lesions (SALs) present a less well-correlated association. In this study, SALs showed significant differences when compared with the features observed in subjects without possible asbestos-related pulmonary fibrotic changes. Minimal bronchioloalveolar fibrotic changes with concomitant presence of ABs can be considered a mild pneumoconiotic lesion (AG1), and SALs may be regarded as an additional indicator of asbestos exposure.