Lung Cancer

Question 1

How common is lung cancer and what is the biggest cause

Answer 1

• 3rd most common
• 80% by cigarette smoking

Question 2

How does lung cancer present histologically ?

Answer 2

Adenocarcinoma (around 40%)
Squamous cell carcinoma (around 20%)
Large-cell carcinoma (around 10%)
Small cell (around 20%) - has neurosecretory granules that release neuroendocrine hormones lead to paraneoplastic syndromes.

Question 3

Signs and symptoms?

Answer 3

Shortness of breath
Cough
Haemoptysis (coughing up blood)
Finger clubbing
Recurrent pneumonia
Weight loss
Lymphadenopathy – often supraclavicular nodes are the first to be found on examination

Question 4

Investigations of lung cancer

Answer 4

• chest x ray
• CT scan- contrast enhanced
  -PET-CT
  -Bronchoscopy
• Histological

Question 5

Treatment options

Answer 5

Surgery- 1st line in non small cell lung cancer (lobectomy) or (segmentectomy)
Radiotherapy
Chemotherapy

Question 6

Extrapulmonary manifestations

Answer 6

-recurrent laryngeal nerve palsy- cancer pressing on nerve
-Phrenic nerve palsy- causes diaphragm weakness
-Superior vena cava obstruction- facial swelling, difficulty breathing and distended veins.“Pemberton’s sign” is where raising the hands over the head causes facial congestion and cyanosis (emergency)
-Horner’s syndrome
-Syndrome of inappropriate ADH (SIADH) - ADH secretion by cancer
-Hypercalcaemia- PTH from squamous cell
-Limbic encephalitis - small cell causes antibodies to brain tissue which causes inflammation
-Lambert Eaton Myasthenic syndrome for small cell
- hypertrophic pulmonary osteoarthropathy for squamous cell

Question 7

What is -Lambert Eaton Myasthenic syndrome ?

Answer 7

-is a result of antibodies produced by the immune system against small cell lung cancer cells.
-antibodies also target and damage voltage-gated calcium channels sited on the presynaptic terminals in motor neurones.
- leads to weakness, intraocular muscles, reduced tendon reflexes (post tetanic potentiation)
-older smokers with symptoms of Lambert-Eaton syndrome consider small cell lung cancer.

Question 8

What is mesothelioma?

Answer 8

-lung malignancy affecting the mesothelial cells of the pleura.
-. It is strongly linked to asbestos inhalation.
- Latent period between exposure and development