Lung Ca

• Lung cancer is the third most common cancer in the UK
• Histological types of lung cancer can be broadly divided into Small-cell lung cancer and non-small cell lung cancer
• Non-small cell lung cancer (80%):

  • Adenocarcinoma (40%) - more common in non smokers and metastasises early
  • Squamous cell carcinoma (20%) - More common in smokers and metastasises late
  • Large cell carcinoma - more common in smokers
  • Mesothelioma - affecting the mesothelial cells of the pleura, strongly associated with asbestos inhalation
• Small cell lung cancer:

  • More common in older smokers
  • Metastasise early
  • Responsible for multiple paraneoplastic syndromes
• Presentation:

  • SOB
  • Cough (chronic)
  • Haemoptysis
  • Recurrent pneumonia
  • Weight loss
  • Lymphadenopathy - often supraclavicular
  • Finger clubbing
• Extrapulmonary manifestations:

  • Recurrent laryngeal nerve palsy - horse voice (usually pancoast tumour)
  • Horner’s syndrome: due to a Pancoast tumour in the lung apex infiltrating the brachial plexus.
  • SVC obstruction - facial swelling and distended neck/upper chest vessels
  • Paraneoplastic syndromes
• Small cell lung cancer can secrete ectopic ADH leading to SIADH - presents with hyponatraemia

  Small cell lung cancer can also secrete ectopic ACTH leading to Cushing's syndrome
• Squamous cell carcinoma can release parathyroid hormone related protein leading to hypercalcaemia
• Lung Ca commonly metastases' to the bones - commonly the spine, pelvis and bones
• The NICE criteria for a 2-week wait referral for lung cancer are:

  • Chest X-ray findings suggestive of lung cancer, or
  • Over 40 years old and unexplained haemoptysis
• Other patients may just need an urgent chest x-ray (within 2 weeks) before a decision to refer on a 2-week wait is made. These patients must be over 40 years old, and have two of the following unexplained symptoms (one if they have ever smoked):

  • Cough
  • Weight loss
  • Appetite loss
  • Dyspnoea
  • Chest pain
  • Fatigue
• Lab investigations:

  • FBC: may show anaemia.
  • LFTs: raised ALP and GGT may indicate hepatic metastases, raised ALP may indicate bone metastases.
  • U&E: in order to know the patient’s baseline before treatment. Hyponatraemia may be due to syndrome of inappropriate antidiuretic hormone secretion (SIADH), which is more common in small cell carcinoma.
  • Serum calcium: elevated with the secretion of PTH-related protein (PTHrP), which is more common in squamous cell carcinoma
• Chest X-ray: first-line investigation in suspected lung cancer. May show single or multiple opacities, pleural effusion and/or lung collapse
• • CT chest-abdomen-pelvis: used to confirm chest X-ray findings. Consider CT if lung cancer is suspected despite a negative chest X-ray. CT of abdomen and pelvis assesses for metastases.
• Endobronchial ultrasound (EBUS) bronchoscopy can be performed for diagnosis