Lung cancer Flashcards
What is lung cancer?
Lung cancer is a broad term encompassing the main subtypes of primary lung malignancies.
As these abnormal cells grow forming tumours, they impede normal lung function.
Understanding the lungs
• THE LUNGS RESPONSIBILITY IS TO BRING OXYGEN INTO THE BODY AND GET RID OF CARBON DIOXIDE
• THE BREATHING PROCESS
• NASAL CAVITY – TRACHEA – BRONCHI – BRONCHIOLES
– ALVEOLI
• GAS EXCHANGE OCCURS AT THE ALVEOLI MOVING OXYGEN INTO OUR BLOOD FOR TRANSPORT AROUND THE BODY
• AT THIS POINT CO2 LEAVES OUR BODY THROUGH EXHALING
• OUR LEFT LUNG HAS 2 LOBES, OUR RIGHT HAS 3.
Risk factors for lung cancer
AGE
GENETICS
TOBACCO SMOKING
DIET & ALCOHOL
CHRONIC INFLAMMATION FROM INFECTIONS & OTHER MEDICAL CONDITIONS
IONISING RADIATION
OCCUPATIONAL EXPOSURES – ASBESTOS, METALS, SILICA AIR POLLUTION – GEOGRAPHIC LOCATION
Signs and symptoms of lung cancer
Haemoptysis New or changed cough Shortness of breath or difficulty breathing Weight loss/loss of appetite Chest/shoulder pain Fatigue Horseness Fever
DD for lung cancer
Benign lung tumours: Hamartomas Carcinoid lung tumours Granuloma
Metastatic cancer Pneumomediastinum
Pneumonia, empyema, and abscess Pneumothorax, tension and traumatic
Types of lung cancer
LUNG SUB-TYPES 80% : NON-SMALL CELL LUNG CARCINOMA (NSCLC) - Adenocarcinoma - Squamous Cell Carcinoma - Large Cell Carcinoma
15% SMALL CELL CARCINOMA
Types of NSCLC
ADENOCARCINOMA (35%) ◦ Most common ◦ Normally peripheral SQUAMOUS CELL CARCINOMA (30%) ◦ Poor prognosis
LARGE CELL CARCINOMA (15%)
◦ Peripherally located
◦ Usually very large (>4cm)
Adneocarcinomas
Comprises around 40% of all lung cancer
Arises from small airway epithelial, type II alveolar cells, which secrete mucus and other substances
Adenocarcinoma is the most common type of lung cancer in smokers and non smokers in men and women
Tends to occur in the periphery of the lung
tends to grow slower and has a greater chance of being found before it has spread outside of the lungs
Squamous cell carcinomas
Comprises 25–30% of all lung cancer cases
Arises from early versions of squamous cells in the airway epithelial cells in the bronchial tubes in the centre of the lungs
Strongly correlated with cigarette smoking
Large cell carcinomas
Accounts for 5–10% of lung cancers
Often begins in the central part of the lungs, sometimes into nearby lymph nodes and into the chest wall as well as distant organs
Strongly associated with smoking
Staging NSCLC
Clinicians use a staging system for lung cancer called TNM:
T – size of tumour
N – spread of cancer to the lymph nodes
M – spread to another area (metastases)
SCLC
Arise from neuroendocrine cells which form part of the LINING of the bronchi
VERY aggressive
Grow quickly and spread via the bloodstream to the liver, lung, bones and brain. Metastasize to the mediastinal lymph nodes quite early.
UNLIKE THE TNM STAGING FOR NSCLC, THERE ARE ONLY TWO GROUPS sclc ARE DIVIDED INTO – ‘LIMITED DISEASE’ & ‘EXTENSIVE DISEASE’
◦ limited disease: the tumour involves only one half of the chest and the lymph nodes draining that half of the chest
◦ extensive disease: any cancer more advanced than this
Pulmonary mets
- Cancer cells can move in the body through the bloodstream or the lymph system - Most common sites of primaries:
- Breast Cancer
- CRC
- RCC
- HNSCC
- Wilm’s Tumour
- Neuroblastoma
CXR for lung cancer
CHEST XRAY
◦ Widespread availability, often the first modality used.
◦ Low sensitivity compared to CT
◦ Often appears as a speculated lesion
◦ May also be inferred from other pathology, unresolved pneumonia, lobe collapse.
CT for lung cancer
- EASILY ACCESSIBLE
- FAST, PAINLESS, NON INVASIVE
- 3-DIMENSIONAL CHEST VIEW
- ALLOWS FOR ACCURATE MEASUREMENT
- USES IONISING RADIATION
- MODALITY OF CHOICE FOR STAGING
- SOMETIMES, DUE TO SURROUNDING
ATELECTASIS IT IS HARD TO DELINEATE THE
TUMOUR MARGINS - SIZE AND INVOLVEMENT OF LYMPH NODES
