Chest ultrasonography in health surveillance of asbestos related pleural disease

Abstract

High resolution computed tomography, (HRCT), is currently considered the diagnostic gold standard to diagnose early stage malignant pleural mesothelioma and other non-malignant pleural conditions, but it is expensive and exposes the patient to radiation dose. In a screening and population medicine perspective, Thoracic Ultrasounds may become a valuable alternative because it can detect minimal changes in pleural surface, is widely available and safe.On these bases, we therefore validated thoracic US in subjects with history of exposure to asbestos, having HRCT as the reference standard.One hundred-fifty subjects were screened and 117 were recruited. Pleural abnormalities at US and/or HRCT were detected in 66 out of 117 subjects (prevalence=57%), and their prevalence was unrelated to both mansion and smoking habit, while mean age and mean length of exposure were higher in those having pleural abnormalities (age=47±5 vs 44±6years, p<0.05;years of exposure=20±7 vs 17±5, p<0.05). Thirteen out of 19 subjects with pleural abnormalities at HRCT were also identified by thoracic US, whereas 47 participants had lesions seen at US, but not at the HRCT scan. Positive and negative percent agreement were 66.6% and 51.8%, respectively; the McNemar’s test for equality showed a p-value <0.001.In conclusion, chest US might complement HRCT in the health surveillance of asbestos exposed population to detect earlier lesions or to follow up US approachable lesions. Further research is needed to clarify whether this approach may enhance early recognition of pleural mesothelioma and ameliorate prognosis.