Neoplasms of Lung and Pleura Dr. Raid Jastania

Lung Neoplasms Neoplasm: –new growth –Monoclonal proliferation –Genetic defect in genes controlling growth –Oncogens, tumor suppressor genes, genes regulating apoptosis, DNA repair genes –Benign and Malignant –Features of malignancy Anaplasia, invasion, rapid growth, metastasis

Lung Neoplasm Primary, Secondary Benign, malignant Primary neoplasms: –Arise from any cell type (epithelial, mesenchyml….) –95% arise from bronchial epithelium (Bronchogenic carcinoma) –Others: neuroendocrine cells, mesenchymal cells

Case

What is the differential diagnoses of Mass lesion in the Lung

Clinical Presentation Mass lesion: incidental, asymptomatic, or causing mass effect Dysfunction of the involved organ Invasion of the adjacent structures Metastasis Paraneoplstic syndromes

Hamartoma of lung Not neoplastic, but mass lesion Discrete small peripheral nodule seen incidentally on x-ray on chest Benign, no risk of malignancy Consists of mature tissue in abnormal, disordered organization: cartilage, fat, fibrous tissue, vessels….

Bronchogenic Carcinoma 1 st cause of death due to Cancer Increasing incidence in females M:F ratio is 2:1, age years Strong relation to smoking It is malignant neoplasm arising from the bronchial epithelium Generally bad prognosis with high rate of mortality, 50% presents with metastasis, Overall survival is 14%

Clinical Presentation Commonly presents as lung mass with hilar lymphadenopathy, and symptoms related to lung disease If localized: can be asymptomatic, or presents with persistent cough Mass effect: resulting in respiratory dysfunction: cough, dyspnea, chest pain, hemoptysis Invasion of Pleura resulting in pleural effusion or pleuritis. Invasion of mediastal structures and vessels Mestastasis to brain, liver, adrenals….

Clinical Presentation Paraneoplastic Syndromes –Hypercalcemia due to PTH-related peptide –Cushing syndrome due to ACTH secretion –Syndrome of inappropriate ADH secretion SIADH –Neuromuscular syndrome: peripheral neuropathy, polymyositis –Clubbing of fingers –Thrombophlebitis, non-bacterial endocarditis, disseminated intravascular coagulation DIC

Classification Non-small cell lung cancer –Squamous cell carcinoma –Adenocarcinoma –Large cell undifferentiated carcinoma Small cell lung cancer –Small cell carcinoma Neuroendocrine tumors –Carcinoid –Atypical carcinoid –Small cell carcinoma

Value of the classification Small cell carcinoma Most present with advance disease High grade with fast progression Associated with smoking (almost all) Treatment is palliative Respond to chemotherapy and radiation Non-small cell ca Can present with localized disease Variable behavior, depend on grade Sq ca is related to smoking, Adeno ca is less associated to smoking Treatment can be fro cure Surgery

Etiology and Pathogenesis Common gene defects in lung cancer –SCLC: P53, RB mutation –NSLC: P16/CDKN2A –Adenocarcinoma: K-RAS Lung cancer develop through accumulation of genetic defects –Loss of 3p is very early event, occurs as a result of smoking

Etiology and Pathogenesis Smoking: –90% of lung caner occurs in smokers –The risk shows linear increase with the smoking intensity (pack-years) –60x risk in a person with 40 pack-years smoking –2x risk in passive smokers Others: asbestos, vinyl chloride… Genetic susceptibility

Etiology and Pathogenesis Progression of lesions due to smoking: –Normal respiratory mucosa –Basal cell hyperplasia –Squamous metaplasia –Squamous dysplasia –Carcinoma in-situ –Invasive squamous cell carcinoma

Morphology Bronchial epithelium Small mass arising from the bronchial epithelium Invasion of submucosa and underlying lung tissue Pushing and invasive borders Central necrosis, hemorrhage, cavitation Metastasis to lymph nodes: lobar, bronchial, hilar, mediastinal, cervical, supraclavicular Hematogenous spread: brain, liver, adrenal, bone… Body cavity metastasis: pleura

Squamous cell carcinoma M>F Central mass, with areas of necrosis, and cavitation Hilar lymphadenopathy Distal obstruction, atelectasis Malignant cells in sputum and bronchoalveolar lavage Grade: well, moderate, poor differentiation Paraneoplstic syndromes

Adenocarcinoma Less associated with smoking Usually small, peripheral lung mass with gray gelatinous surface Grade: well, moderate, poor differentiation Metastasize early Special pattern: bronchioloalveolar carcinoma BAC

Large cell undifferentiated carcinoma High grade tumor Poorly differentiated

Small cell carcinoma Central mass with hilar and mediastinal lymphadopathy Small cells, nuclear molding, fine chromatin, mitosis, necrosis, neuroendocrine features High grade Respond to chemotherapy and radiation

Special presentation of lung cancer Virchow node: supraclavicular node enlargement due to metastasis Superior vena cava syndrome: obstruction of the SVC by cancer Horner syndrome: ipsilateral enophthalmos, ptosis, meiosis, anhidrosis. It is caused by tumor involving the sympathetic nerves Pancoast tumor: lung cancer involving the upper lobe.

Carcinoid Tumor arising from the endocrine cells (Kulchitsky cells) Mean age 40 years Good prognosis Mass lesion: –Intraluminal mass in large bronchus –Peribronchial mass (collar-button lesion) Metastasis: rare 5-15%

Carcinoid Micro: uniform cells with rounded nuclei, salt-and-pepper chromatin Atypical carcinoid: if the tumor cells show mitosis and necrosis 5 year survival: %

Malignant Mesothelioma Arise from parietal or visceral pleura or peritoneum 50% has relation to Asbestos, latent period years Pleural fibrosis – plaque – localized mass – mass encasing the lungs Bad prognosis

Diagnosis Clinical presentation Sputum Pleural fluid Fine needle aspiration Biopsy Resection