1. TUMORS OF THE LUNG * Classification: 1. Benign tumors: - Papilloma. - Fibroma. - Chondroma. 2. Locally malignant tumors: - Bronchial carcinoid 3. Malignant tumors: A. Primary M. tumors: - Bronchogenic carcinoma. - Lymphoma. - Sarcomas. B. Secondaries.

2. BRONCHOGENIC CARCINOMA BRONCHIAL CARCINOID 1. Age Above 40 Ys. 20-40 Ys. 2. Incidence 2. Incidence - The commonest 1ry M. tumor of the lung. - More in males. - Less common (1-5% of lung tumors). - Equal in both sexes. - Equal in both sexes. 3. Predisposing factors - Cigarette smoking. - Exhaust fumes of tar and diesel. - Bronchiectasis. - Asbestosis. Not related to cigarette smoking or environmental factors.

3. BRONCHOGENIC CARCINOMA BRONCHIAL CARCINOID 4. Cell of origin Epithelial cells of bronchial mucosa. Neuroendocrine cells “ kulchitsky cells ” of bronchial mucosa (APUD system). 5. Gross a. Central (hilar) type: 85%. - Arises from the main bronchus. - Forms a polypoid, ulcerative, or infiltrative growth. b. Peripheral type: 15%. - Arises from peripheral bronchi or bronchiole. - Forms a single or multiple masses. Site: near the hilum, arise from a main bronchus. N/E: a brownish yellow spherical mass projects into the bronchial lumen. May infiltrtae the lung tissue and appears as dumbell-shaped mass. The covering mucosa is usually intact.

5. BRONCHOGENIC CARCINOMA BRONCHIAL CARCINOID 6. M/P * One of the following; 1. Squamous cell carcinoma (describe) 2. Adenocarcinoma (describe). 3. Small cell carcinoma (oat cell carcinoma): Sheets of malignant small cells, having increased nuclear/cytoplasmic ratio and frequent mitosis. The sheets are separated by fibrous tissue stroma. Wide areas of necrosis. 4. Large cell carcinoma: sheets of large sized malignant cells, having anaplastic features. The sheets are separated by scanty fibrous tissue stroma. - Nests, cords or masses of small cuboidal cells separated by delicate fibrous stroma. - The cells are uniform with rounded nuclei.the cytoplasm contain argyrophilic granules that stain with silver.

6. Small cell (oat cell) carcinoma

7. BRONCHOGENIC CARCINOMA BRONCHIAL CARCINOID 7. Effects and complications 1. Spread: a. Local: lung tissue, pleura, esophagus, phrenic nerve, recurrent laryngeal nerve, SVC & pericardium. b. Lymphatic: to hilar, mediastinal, supraclavicular L.Ns. c. Blood spread: through pulmonary artery to the lung and through pulmonary veins to systemic organs. 2. Hemoptysis. 3. Bronchial obstruction: leads to emphysema, atelectasis, retained secretion and suppuration, pneumonia. 4. Paraneoplastic syndrome. 1. Malignant transformation with metastasis. 2. Hemoptysis. 3. Bronchial obstruction. 4. Carcinoid syndrome.

8. LUNG METASTASES (SECONDARIES) More common than the 1ry tumors. *Two forms I. Metastases reach through pulmonary artery: From malignant melanoma, hepatoma, encocrine carcinomas, urogenital carcinoma (renal cell carcinoma and testicular tumors), sarcomas and leukaemias. N/E: multiple nodules, variable in size scattered all over the lung lobes especially at the periphery. Metastases from RCC and seminoma are large in size and spherical in shape called “ cannon- ball secondaries ”. M/P: like its 1ry. II. Metastases reach through lymphatics: From cancer breast, abdominal carcinomas and lymphoma.