Week 4 - Pathology of Lung Cancer Flashcards
What is the aetiology of lung cancer? (5)
Tobacco, asbestos, environmental radon, other occupational factors, air pollution,
How many known chemical compounds and carcinogens is found in a cigarette?
4000+ chemical compounds, 60+ recognised carcinogens
How are genetics involved in the likelihood of developing lung caner? (2)
individual metabolism of pre-carcinogens
nicotine addiction
What are the 2 main pathways to carcinogenesis?
lung periphery - bronchioloalveolar stem cells transform into cancer cells and then invade - adenocarcinoma
central lung - bronchial epithelial stem cells transform to cancer cells and form squamous cell carcinoma
What are the types of tumours? (5)
benign, lymphoma, sarcoma, carcinoid (low grade malignancy), bronchial gland tumour (rare)
What are the 4 types of carcinoma of the lung?
NSCLC - squamous, adenocarcinoma, large cell carcinoma
SCLC - small cell carcinoma
What is the most prevalent carcinoma?
squamous cell carcinoma - 40-60%
Which tumour is surgery commonly not carried out on and why?
SCLC - its fast growing and metastasises quickly
What are some features of primary lung cancer?
grows clinically silent for many years, presenting late in its natural history. usually found by accident in an alternative investigation
What is the issue with symptomatic lung cancer?
It’s fatal
What are the local effects of bronchial obstruction?
collapse of bronchi, bronchiectasis, endogenous lipid pneumonia
What is endogenous lipid pneumonia?
bronchial obstruction may lead to breakdown of destroyed alveolar walls, which release cholesterol as debris. lipid gathers in lung and cause inflammation and pneumonia
What are the local effects of tumour to the pleura?
inflammation from infection, malignancy in pleural wall,
What issues can direct invasion of lung cancer cause?
- Invade chest wall directly
- Phrenic nerve - diaphragmatic paralysis
- Laryngeal nerve - hoarse voice and bovine cough - cant close epiglottis
- Pancoast tumour - brachial plexus damage
- nerve damage - Horners syndrome
What is horners syndrome?
cervical sympathetic chain damage - paralysis on one side of face - droopy eyelid and cant sweat
What is the danger of lymph node metastasis?
lymphangitis carcinomatosa - inflammation of lymph vessels caused by malignancy
What are the 4 wide local effects of tumours?
Bronchial obstruction,
pleural issues,
lymph node invasion,
direct invasion nerve issues
What are the skeletal distant effects?
- clubbing
- HPOA (hypertrophic pulmonary osteoarthropathy)
What are the endocrine distant effects? (4)
- SCLC - abnormal ACTH - too much cortisol - and SIADH - too much adh - keep water
- Squamous cell - PTH imbalance - hypercalcaemia
- Carcinoid syndrome - cancer spreads to liver, serotonin released
- Gynaecomastasia - man boobs
What are the neurological distant effects? (4)
Polyneuropathy, encephalopathy (agent affecting functioning of brain) , cerebellar degeneration, myasthenia
What are the dermatological distant effects?
dermatomyositis, acanthosis nigricans
What are the haematolytic distant effects?
granulocytosis, eusinophilia, DIC (disseminated intravascular coagulation - blood clots)
What is a renal distant effects?
nephrotic syndrome - passing too much protein in urine
What main investigations are carried out for lung cancer? (5)
CXR, bronchoscopy, trans-thoracic fine needle aspiration, core biopsy (larger sample), pleural effusion cytology and biopsy
