L16. Lung Cancer Pathology Flashcards
What are the general epidemiological features of Lung cancer
Most common cause of cancer death but 5th most common incidence.
Strong link to smoking- length relates to incidence. Environmental and genetic factors as well.
Describe relationship between morphological and molecular transformation of benign bronchial epithelium to neoplasm
Step-wise progression of morphological changes into dysplasia–>carcinoma in situ–> then metastatic are associated with molecular changes in chromosomes, regulatory genes
What are the different classifications of lung carcinomas and the cells they are related to - (combined pattern makes up 5-10% of cancers)
Small cell lung cancer: neuroendocrine cell in epithelial lining
Non small cell lung cancer:
- Squamous cell carcinoma: basal cell in proximal/major bronchi
- Adenocarcinoma: type 2 alveolar cells
- Large cell carcinoma
What is the importance of the histopathological classification of primary lung cancer
Reflects the cells that cancers have arisen from.
- The behaviour of those cancers, with different patterns of gene mutation- molecular pathology as there is heterogeneity in the genes that drive the cancer
- presentation,
- prognosis
- treatment: targeted therapy (eg. EGFR mutations)
What are some local effects of tumour- relating to the lung and what tumours would cause that
- Cough, dyspnoea: blocked airways
- Obstructive pneumonia: abnormal ciliary clearance
- Haemoptysis: invades mucosal layer and goes into bv
- Chest pain: impinge nerves
What are some effects of local spread of the tumour - just outside the lung and what tumours would cause that
- Pleuritic chest pain: peripheral tumour: invasion into pleural surface
- Pleural effusion: inflammation of peripheral tumour
- Horners syndrome: tumour in apex of lung impinge symp chain
What are some effects of spread of the tumour to the Mediastinum and what tumours would cause that
Hoarse voice: reccurent laryngeal nerve entrapment by tumour in the left hila region.
-Distended jugular vein, hands above the head, impaired drainage of blood from the face- Red face caused by Tumour in mediastinum compression SVC
What are Paraneoplastic syndromes (systemic effects due to compounds secreted by cancers) related to Small and Non small cell lung cancer
Small cell lung cancer:
Cushing syndrome: increased cortisol secondary to ACTH release ; inappropriate
ADH secretion- increased fluid retention - hyponatremia.
Non small cell lung cancer: production of PTH-rp which causing secondary hypercalcaemia
Finger clubbing: loss of normal indentation of nail bed- feature of lung pathology
What is the appearance of
Squamous cell carcinoma, where are tumours more likely found, and predisposing factors
> Appears as Grey, ulcerated lesions in bronchial wall to parenchyma.
Necrosis, cavitation, dysplasia.
Tumours found in major or segmental bronchi
Strong link to smoking: injury to bronchial epithelium
What is the appearance of Adenocarcinoma where are tumours more likely found, and predisposing factors
> Glandular appearance reflecting part of respiratory tract.
Tumours in periphery- in pleural fibrosis or scars.
More common in females, non smoker, w late presentation
What is the appearance of Small cell carcinoma, where are tumours more likely found, and predisposing factors
> Malignant epithelial tumour. haemorrhage, necrosis,
sheets of small round or spindle cells w high mitotic rate. Neuroendocrine features so paraneoplastic syndromes common
caused by Smoking,
Tumour found perihilar region to lymph nodes.
What is Large cell carcinoma and Carcinoid tumour
LCC: Undifferentiaed tumour, not squamous or adenocarcinoma
Carcinoid: distinct neuroendocrine tumour not linked to smoking.
What is Pulmonary metastatic disease
More common, multiple lesions of 2ndary tumours with histology of the primary tumour.
What is malignant mesothelioma: causes, features
> Mesothelial cell tumour in pleura with both epithelial and sarcomatous element. Aggressively encases lung.
From asbestos fibre exposure, with long latency
