Asbestos-related lung disease Flashcards
What diseases can asbestos cause?
Asbestos can cause a variety of lung diseases from benign pleural plaques to mesothelioma.
What are pleural plaques?
Pleural plaques are benign and do not undergo malignant change. They do not require any follow-up.
They are the most common form of asbestos-related lung disease and generally occur after a latent period of 20-40 years.
What is pleural thickening?
Asbestos exposure may cause diffuse pleural thickening in a similar pattern to that seen following an empyema or haemothorax. The underlying pathophysiology is not fully understood.
What is asbestosis?
Asbestosis is related to the length of exposure, with a latent period typically of 15-30 years. It typically causes lower lobe fibrosis.
What are the features of asbestosis?
Features include dyspnoea and reduced exercise tolerance, clubbing, bilateral end-inspiratory crackles, and lung function tests showing a restrictive pattern with reduced gas transfer.
How is asbestosis treated?
Asbestosis is treated conservatively; no interventions offer a significant benefit.
What is mesothelioma?
Mesothelioma is a malignant disease of the pleura, with crocidolite (blue) asbestos being the most dangerous form.
What are the possible features of mesothelioma?
Possible features include progressive shortness-of-breath, chest pain, and pleural effusion.
What is the prognosis for mesothelioma?
The prognosis is very poor, with a median survival from diagnosis of 8-14 months.
What is the relationship between asbestos and lung cancer?
Lung cancer is the most common form of cancer associated with asbestos exposure and has a synergistic effect with cigarette smoke.
Why is smoking cessation important for those exposed to asbestos?
Smoking cessation is very important as the risk of lung cancer in smokers who have a history of asbestos exposure is very high.
What is mesothelioma?
Mesothelioma is a cancer of the mesothelial layer of the pleural cavity that is strongly associated with asbestos exposure. In a small percentage of cases, other mesothelial layers such as those in the abdomen may be affected.
What are the features of mesothelioma?
Features include dyspnoea, weight loss, chest wall pain, clubbing, and 30% present as painless pleural effusion. Only 20% have pre-existing asbestosis.
What is the history of asbestos exposure in mesothelioma cases?
History of asbestos exposure is found in 85-90% of cases, with a latent period of 30-40 years.
What is the basic pathology of mesothelioma?
It is a malignancy of mesothelial cells of the pleura, with metastases to the contralateral lung and peritoneum. The right lung is affected more often than the left.
How is mesothelioma investigated or diagnosed?
Suspicion is raised by a chest x-ray showing either a pleural effusion or pleural thickening. The next step is normally a pleural CT.
What should be done if a pleural effusion is present?
Fluid should be sent for MC&S, biochemistry, and cytology, but cytology is only helpful in 20-30% of cases.
What is the role of local anaesthetic thoracoscopy in mesothelioma diagnosis?
Local anaesthetic thoracoscopy is increasingly used to investigate cytology negative exudative effusions as it has a high diagnostic yield (around 95%).
What is done if an area of pleural nodularity is seen on CT?
An image-guided pleural biopsy may be used.
What are the management options for mesothelioma?
Management includes symptomatic treatment, industrial compensation, chemotherapy, and surgery if operable.
What is the prognosis for mesothelioma?
The prognosis is poor, with a median survival of 12 months.
