Pathological features: ⁻ Grossly, the silicotic nodule is gray-black hard, and brittle and has concentric rings of hyalinized collagen in cross section. ⁻ Nodules are found mainly along lymphatic pathways, especially around the hilum and in the upper lobes. Clinical features: ⁻ exposed to massive amounts of dust, acute lung disease. ⁻ Chronic pulmonary fibrosis with a mild restrictive ventilatory defect, slowly progressive dyspnea, and pulmonary hypertension (cor pulmonale). Complications: ⁻ progressive massive fibrosis ⁻ incidence of tuberculosis (macrophage function) ⁻ silicosis is also associated with an increased incidence of autoimmune disease.
5. THE ETIOLOGY, PATHOGENESIS AND PATHOLOGICAL FEATURES OF CHRONIC COR PULMONALE. Chronic corpulmonale: is right ventricular hypertrophy because of lung disease or disorder. Increased pulmonary blood pressure, or flow, or both, increased pulmonary vascular resistance, left heart resistance to blood flow may all lead to corpulmonale. ETIOLOGY: Chronic obstructive disease, including chronic bronchitis, emphysema, asthma, bronchiectasis, pneumoconiosis, may lead to corpulmonale. Pulmonary hypertension in which destruction of portions of pulmonary vascular bed, vasoconstrivte effects of hypoxemia, and respiratory acidosis which may lead to the hypertension. PATHOLOGICAL FEATURES: Right ventricle is thickened with an accompanying increase in the weight of the heart. The right ventricular wall may reach a thickness of more than 1.5 cm, and the weight of the heart may be increased to 500 or to 700g. Thickness of right ventricular wall exceeding 0.5 in which normal state it would be 0.2-0.3, under the pulmonary artery valve 2 cm is the diagnostic criterion of chronic corpulmonale in pathology.
6. THE ETIOLOGY, CLASSIFICATION, GROSS TYPES, SPREAD AND CLINICAL FEATURES OF CARCINOMA OF THE LUNG. ETIOLOGY: Due to carcinogens, cigarette smoking, urban pollution, radiation, molecular genetics, and scar cancer. CLASSIFICATION: A. SQUAMOUS CELL CARCINOMA: ⁻ Squamous carcinoma arises from the bronchial epithelium. ⁻ It is characterized by intercellular bridges (desmosomes) between tumor cells, and keratinization of the cytoplasm. ⁻ Squamous carcinoma has a strong male predominance, is strongly associated with cigarette smoking. ⁻ Squamous carcinoma tends to remain localized more than the other types, resulting in large masses in the lung. B. ADENOCARCINOMA: ⁻ Adenocarcinoma of the lung, shows glandular differentiation or secretion of mucin by the tumor cells, showing acinar, papillary, bronchioloalveolar or solid with mucin growth pattern or a mixture of these patterns. 13 | P a g e