From the Guidelines
Noncalcified pleural thickening requires a systematic evaluation approach beginning with a thorough clinical history focusing on asbestos exposure, infections, or inflammatory conditions. Initial imaging should include chest radiographs, followed by CT scans for better characterization of the thickening and to rule out malignancy, as suggested by 1. If the thickening is focal or suspicious, a PET-CT may be indicated to assess metabolic activity. Diagnostic procedures often include:
- Thoracentesis if pleural fluid is present, with a sensitivity rate for malignancy of about 72% when at least two pleural fluid specimens are submitted, as reported by 1
- Pleural biopsy (either CT-guided, ultrasound-guided, or via thoracoscopy) to obtain tissue for histopathological examination, with a sensitivity rate ranging from 80% to 99% and a specificity rate ranging from 93% to 100%, as stated by 1 Treatment depends on the underlying cause, including:
- Antimicrobial therapy for infectious etiologies
- Anti-inflammatory medications for inflammatory conditions
- Observation with periodic imaging for benign asbestos-related pleural disease
- Systemic therapy, such as chemotherapy, for malignant pleural effusions due to tumors likely to respond to chemotherapy, as mentioned by 1 Symptomatic cases with significant restrictive lung function may require decortication surgery to remove the thickened pleura and improve lung expansion. The prognosis varies based on etiology, with benign causes generally having better outcomes than malignant ones, and regular follow-up with serial imaging is essential to monitor for progression or development of complications, particularly in patients with asbestos exposure who have increased risk for mesothelioma, as noted by 1.
From the Research
Evaluation of Noncalcified Pleural Thickening
- Noncalcified pleural thickening can be evaluated using various imaging modalities, including computed tomography (CT) and magnetic resonance imaging (MRI) 2.
- MRI has been shown to be useful in distinguishing malignant from benign pleural disease, with a sensitivity of 98% and a specificity of 92% 2.
- The morphologic features of pleural lesions, such as mediastinal pleural involvement, circumferential pleural thickening, nodularity, and irregularity of pleural contour, can be suggestive of a malignant cause on CT and MR images 2.
Treatment Approach
- The treatment approach for noncalcified pleural thickening depends on the underlying cause, which can include malignant pleural mesothelioma, primary pleural lymphoma, or pleural tuberculosis 3, 4, 5.
- For malignant pleural mesothelioma, a multimodality therapy approach, including pleurectomy/decortication, hyperthermic pleural lavage with povidone-iodine, prophylactic radiotherapy, and systemic chemotherapy, has been shown to be safe and well-tolerated 3.
- For primary pleural lymphoma, treatment may involve thoracoscopic pleural biopsy and subsequent chemotherapy or radiation therapy 4.
Clinical Features and Associations
- Pleural thickening is a common finding on routine chest X-rays, and its prevalence increases with age, ranging from 1.8% in teenagers to 9.8% in adults aged 60 years and older 6.
- Pleural thickening is more common in males than in females and in current smokers or ex-smokers than in never smokers 6.
- A tall, thin body shape may predispose to pleural thickening, suggesting that disproportionate perfusion, ventilation, or mechanical forces in the lungs may play a role in its development 6.