1. In the name of GOD

2. Asbestos-Related
Disease

3. Asbestos Exposure General
Salts of salicic acid
90% of asbestos in USA is white asbestos (chrysotile)
Occurs in :
Automotive workers-brake linings
Shipfitters
Construction workers

4. Asbestos-Related Disease Types of Fibers
Chrysotile (white asbestos)–benign
Crocidolite (blue/black asbestos) in South Africa/Australia–malignant
Crocidolite-small fibers-associated with most pleural disease

5. Asbestos-Related Disease Types of Fibers:
Serpentins
Chrysotil (white asbestos)
Amphibole
Crocidolith (blue)
Amozith (brown)
Anthophylith
Tremolith

6. Asbestos particles invoke a hemorrhagic response in lung
Asbestos-Related Disease Pathophysiology
Asbestos particles invoke a hemorrhagic response in lung
Fibers then coated with a ferritin-like material resulting in ferruginous bodies
Damage to respiratory bronchioles and alveoli

7. Asbestos-Related Disease Types of
Asbestos-related Pleural Disease
Asbestosis
Asbestos-related Malignancies

8. Asbestosis (pulmonary parenchymal fibrosis)
1- Almost always involves lower lobes at subpleural areas
2-As the disease progresses, fibrosis and volume loss ensue
3-Honey-combing in lower lobe subpleural areas
4-Tracheobronchial nodal involvement is unusual
5-PMF is very uncommon

9. Asbestos-Related Pleural Disease
Pleural plaques
Diffuse pleural thickening
Pleural calcification
Pleural Effusion

10. Asbestos-Related Pleural Disease Incidence of Pleural Disease
Almost all have some pleural involvement
Pleural plaque 65%
Diffuse pleural thickening 17%
Calcification 50%
Effusion 21%
Pleural involvement without parenchymal disease is common

11. Asbestos-Related Pleural Disease
Pleural Plaques-1
Affects submesothelial layer of parietal pleura
Bilateral, mid-lung zone
Between 7th and 10th ribs
Diaphragmatic pleura
Spares apices

12. Asbestos-Related Pleural Disease Pleural Plaques-2
Plaques don’t usually calcify
Plaques alone are not associated with malignancy
Appear either in “profile” or “en face”

13. Asbestos-Related Pleural Disease Diffuse Pleural Thickening-1
Diffuse thickening of parietal pleura
Involves diaphragmatic pleura, extends up lateral chest wall
Commonly obliterates costophrenic angles
Spares apices of lungs
DDX from TB

14. Asbestos-Related Pleural Disease Diffuse Pleural Thickening-2
Frequently the sequela of benign pleural effusion
Associated with rounded atelectasis

15. Rounded Atelectasis
Part of peripheral parenchyma invaginated into the penetrating fibrotic visceral pleura, so that part of the parenchyma is entrapped and becomes atelectatic

16. HRCT findings of Rounded Atelectasis
1-Continuing with areas of diffuse pleural thickening
2-Lenticular or wedge-shaped
3-Comet-tail sign
4-evidence of volume loss in the affected lobe often associated with hyperlucency of the adjuscent lobe

17. Asbestos-Related Pleural Disease
Pleural Effusion
Effusion alone may occur early in disease (first 15 years) in about 3% of cases
Exudative
May be associated with chest pain
Involves visceral pleura as well
Does not mean mesothelioma
May be associated with rounded atelectasis

18. Diagnostic Criteria: 1-Exposure history for asbestos
2- Ruling out other causes
3-Failing to detect tumor in a 3 years follow-up

19. Pathological description:
Chronic fibrinous pleuritis with low cellularity
Prognosis:
Good with a self-limited course
Recurrence may occur

20. Asbestosis General Reserved for parenchymal lung disease
Fibrosis begins around bronchi and progresses outward

21. Asbestosis
Interstitial lung disease
Rounded atelectasis

22. Asbestosis Location
More common in lower lungs
More common subpleural

23. Asbestosis X-ray Opacities are small and irregularly shaped
Not rounded as in silicosis
Prominent septal lines around 2° lobules
Cardiac silhouette may become shaggy
Hilar lymph nodes rarely affected
DDx from silicosis

24. Asbestosis HRCT
Multiple subpleural dot-like nodularities=subpleural lines
Fibrous bands
Subpleural pulmonary arcades
Honeycombing
Thickened interlobular lines
Ground-glass appearance

25. Asbestos-Related Malignancies
Bronchogenic carcinoma
Mesothelioma
Benign
Malignant
Carcinoma of the larynx or stomach

26. Asbestos-Related Disease Lung Cancer
Either squamous cell or adenocarcinoma
Bronchogenic ca is almost always associated with cigarette smoking
90x more common in smokers, 5x more common in
Frequently at lung base
Associated with increased risk of stomach cancer
non-smokers

66. Thank you…