PLEURAL LESIONS. Inflammatory Pleural Lesions. MESOTHELIOMA. Rare tumor, 50% of cases are related to occupational exposure to asbestos for 25-40 ys. Shipyard workers, miners and insulator. Living near asbestos factory or being relative of an asbestos workers. Latent period : 25-40 y.
Microscopically, the fibrous pleural plaque is composed of dense layers of collagen
The dense white encircling tumor mass is arising from the visceral pleura and is a mesothelioma. These are big bulky tumors that can fill the chest cavity.The risk factor for mesothelioma is asbestos exposure. However, mesothelioma is rare even in persons with asbestos exposure. Asbestosis more commonly predisposes to bronchogenic carcinomas, increasing the risk by a factor of five. Smoking increases the risk for lung cancer by a factor of ten. Thus, smokers with a history of asbestos exposure have a risk 50 fold greater likelihood of for developing lung cancer.
Mesotheliomas have either spindle cells or plump rounded cells forming gland-like configurations, as seen here at high power microscopically. They are very difficult to diagnose cytologically.
This is the causative agent for asbestosis. This long, thin object is an asbestos fiber. Many houses and offices still contain building materials with asbestos, particularly insulation, so care must be taken when doing remodelling or reconstruction.