Pathological Principles of Pleura - PDF

PLEURAL PATHOLOGY Prof PT Schubert Division of Anatomical Pathology Department of Pathology Stellenbosch University and NHLS  PLEURA Connective tissue lined by mesothelial cells investing the lung and chest cavity. Visceral pleura : covers the...

PLEURAL PATHOLOGY Prof PT Schubert Division of Anatomical Pathology Department of Pathology Stellenbosch University and NHLS  PLEURA Connective tissue lined by mesothelial cells investing the lung and chest cavity. Visceral pleura : covers the lung Parietal pleura : covers the thoracic cage wall, diaphragm, heart and mediastinum  INFLAMMATION OF THE PLEURA Pleuritis (pleurisy) Causes: Infection : Primary infection : cryptococcus Secondary involvement form pneumonia, TB, lung abscess Penetrating injury Connective tissue disorder Rheumatic fever, Rheumatoid disease, SLE Pulmonary infarct With secondary inflammation of the pleura Lung / pleural neoplasm Inflammation is accompanied an effusion  INFLAMMATION OF THE PLEURA Healing of an inflammatory process: Resolution Adhesions Plaques Mostly secondary to asbestos exposure Asymptomatic patches of thickened pleural by fibrosis Fibrosis Localized thickening due to prev inflammation Diffuse : mostly secondary to asbestosis, mesothelioma, lung carcinoma. Pleural adhesion ASBESTOSIS  COLLECTIONS IN THE PLEURAL CAVITY Air – pneumothorax Fluid (serous fluid) : hydrothorax (pleural effusion) Transudate : low protein Exudate : high protein Blood – haemothorax Lymphatic fluid (Chylothorax) - lymph Pus – pyothorax (empyema)  COLLECTIONS IN THE PLEURAL CAVITY Transudate : low protein Cardiac failure Renal failure Liver failure Exudate : high protein Inflammation Infections Tumours Reactive mesothelial cells and chronic inflammation Reactive mesothelial cells and macrophages Chronic inflammation Eosinophilic effusion Cryptococcus infection Pneumothorax Tension Pneumothorax  PLEURAL TUMOURS Benign tumours – uncommon Solitary fibrous tumour. Proliferation of fibroblastic cells in a dense collagenous stroma Malignant tumours: Primary Mesothelioma Secondary Spread from lung or breast.  MESOTHELIOMA (MALIGNANT) Carcinoma of the mesothelial lining of the pleural cavity. Strong association with asbestos exposure. Especially: crocidolite (blue asbestos) & amosite (brown asbestos). Interval between exposure and mesothelioma = ± 30yrs  MESOTHELIOMA Begins as a nodule , spreads as a confluent sheet to surround (encase) the entire lob/lung. Infiltrates the chest wall and intercostal nerves. Invades lymphatics with spread to hilar nodes Hematogenous spread is less common (in 30%). Histology: Epithelial shaped cells (epithelioid mesothelioma) and spindle shaped cells (sarcomatous mesothelioma) in a fibrous stroma. Median survival : ±11months MESOTHELIOMA MESOTHELIOMA MESOTHELIOMA 55yr old man presents with weight loss and chest pains. CT Scan PLEURAL METASTASIS Metastatic adenocarcinoma Metastatic adenocarcinoma Metastatic squamous cell carcinoma Metastatic small cell carcinoma