Lung Cancer

• Lung cancer is the third most common cancer in the UK, behind breast and prostate cancer
• Smoking is the most significant cause of lung cancer
• Around 80% of lung cancers are thought to be preventable
• Histological types of lung cancer

  • Small-cell lung cancer (SCLC)
  • Non-small-cell lung cancer
  • Adenocarcinoma
  • Squamous cell carcinoma
  • Large-cell carcinoma
  • Other types
• Small-cell lung cancer


  Cells contain neurosecretory granules that release neuroendocrine hormones
• Small-cell lung cancer may be responsible for various paraneoplastic syndromes
• Mesothelioma is a lung malignancy affecting the mesothelial cells of the pleura
• Mesothelioma is strongly linked to asbestos inhalation
• There is a substantial latent period between exposure to asbestos and the development of mesothelioma of up to 45 years
• The prognosis for mesothelioma is very poor
• Chemotherapy can improve survival in mesothelioma, but it is essentially palliative
• Presenting features of lung cancer

  1. Shortness of breath

  2. Cough

  3. Haemoptysis (coughing up blood)

  4. Finger clubbing

  5. Recurrent pneumonia

  6. Weight loss

  7. Lymphadenopathy
• Lung cancer is associated with a lot of extrapulmonary manifestations and paraneoplastic syndromes
• Recurrent laryngeal nerve palsy presents with a hoarse voice
• Phrenic nerve palsy causes diaphragm weakness and presents with shortness of breath
• Superior vena cava obstruction is a complication of lung cancer
• Superior vena cava obstruction presents with facial swelling, difficulty breathing, and distended neck and upper chest veins
• Pemberton’s sign is where raising the hands over the head causes facial congestion and cyanosis
• Superior vena cava obstruction is a medical emergency
• Tumour compression on the superior vena cava presents with facial swelling, difficulty breathing, and distended neck and upper chest veins
• SVC obstruction is a medical emergency
• Horner’s syndrome is a triad of partial ptosis, anhidrosis, and miosis
• Horner’s syndrome can be caused by a Pancoast tumour pressing on the sympathetic ganglion
• Syndrome of inappropriate ADH (SIADH) can be caused by ectopic ADH secreted by small-cell lung cancer and presents with hyponatraemia
• Cushing’s syndrome can be caused by ectopic ACTH secretion by small-cell lung cancer
• Hypercalcaemia can be caused by ectopic parathyroid hormone secreted by squamous cell carcinoma
• Limbic encephalitis is a paraneoplastic syndrome where small-cell lung cancer causes the immune system to make antibodies to tissues in the brain, specifically the limbic system, causing inflammation and symptoms such as short-term memory impairment, hallucinations, confusion, and seizures
• Limbic encephalitis is associated with anti-Hu antibodies
• Lambert-Eaton myasthenic syndrome is caused by antibodies against small-cell lung cancer cells, damaging voltage-gated calcium channels on presynaptic terminals in motor neurones, leading to weakness in proximal muscles and affecting intraocular, levator, and pharyngeal muscles causing symptoms like diplopia, ptosis, slurred speech, and dysphagia
• Lambert-Eaton myasthenic syndrome can also cause dry mouth, blurred vision, impotence, and dizziness due to autonomic dysfunction
• NICE guidelines recommend offering a chest x-ray within 2 weeks to patients over 40 with specific symptoms and signs for suspected cancer
• NICE guidelines recommend offering a chest x-ray to patients over 40 years old with unexplained symptoms, especially in those who have smoked or had asbestos exposure
• Unexplained symptoms listed by NICE guidelines

  • Cough
  • Shortness of breath
  • Chest pain
  • Fatigue
  • Weight loss
  • Loss of appetite
• Chest x-ray is the first-line investigation in suspected lung cancer
• Findings on chest x-ray suggesting cancer

  • Hilar enlargement
  • Peripheral opacity
  • Pleural effusion
  • Collapse
• Staging CT scan of the chest, abdomen, and pelvis is used to assess the stage, lymph node involvement, and presence of metastases in lung cancer
• Staging CT scan should be contrast-enhanced for more detailed information about different tissues
• PET-CT scans involve injecting a radioactive tracer and taking images to visualise metabolically active tissues and identify metastases
• Bronchoscopy with endobronchial ultrasound (EBUS) allows detailed assessment in suspected lung cancer
• Endobronchoscopy with endobronchial ultrasound (EBUS)

  Endoscopy with ultrasound equipment on the end of the scope, allowing detailed assessment of the tumour and ultrasound-guided biopsy