Lung cancer

Question 1

What are the main types of lung cancer? Which is most strongly associated with smoking? Which is most common in non-smokers?

Answer 1

1. Non-small cell lung cancers
   i. adenocarcinoma: most common type overall, most common type in non-smokers, most common type in women
   ii. squamous cell carcinoma: strong associated with smoking
   iii. large cell carcinoma
2. Small cell lung cancer: most strongly associated with smoking

Question 2

Where are lung adenocarcinomas and SCCs usually located in the lung?

Answer 2

• adenocarcinoma: peripheral localisation, with invasion of pleura + mediastinal LNs and distant mets (bone + brain) common
• SCC: central airways localisation (most present as obstructive lesions of bronchus causing infection), local spread is common but widespread mets occur relatively late

Question 3

Which cells do SCLCs arise from?

Answer 3

Kulcitsky cells (pulmonary neuroendocrine cells) - so are associated with several paraneoplastic syndromes

Question 4

Suggest possible risk factors for the development of lung cancer.

Answer 4

1. smoking
2. COPD
3. FHx
4. asbestos/radon gas exposure
5. air pollution

Question 5

A 55yo man presents with a 4/12 history of cough + SOB. He has recently had 2 episodes of blood-tinged sputum. CXR confirms lung cancer. What further investigations are required?

Answer 5

Imaging

1. contrast CT lower neck, thorax + upper abdomen: shows size, location + extent of primary tumour, evaluates for hilar and mediastinal lymphadneopathy and distant mets
2. PET-CT: further Ix

Histology

1. biopsy via bronchoscopy (if endo- or transbronchial lesion), percutaneous transthoracic needle biopsy (if peripheral lesions) or LN biopsy: for definitive diagnosis, typing, subtyping and mutation testing
2. thoracocentesis: if pleural effusion

Other

1. bloods: FBC, U+Es, Ca2+, LFTs, INR
2. PFTs: for all pts undergoing surgery or radial RT
3. EGFR, ALK + ROS1 mutation test

Question 6

What are the management options for a patient with NSCLC?

Answer 6

1. lobectomy or pneumonectomy (best chance of cure but significant morbidity/mortality) OR
2. radiotherapy AND
3. (neo)adjuvant chemo: CISPLATIN + another

OR
4. palliative care: nintedanib (TKI) + doctaxel or immune checkpoint inhibitors e.g. nivolumab

Question 7

What are the management options for a patient with SCLC?

Answer 7

Chemo (CISPLATIN/CARBOPLATIN + ETOPOSIDE) + RT + prophylactic cranial irradiation +/- surgery if limited disease

Question 8

Which paraneoplastic syndrome is commonly associated with squamous cell lung cancer? How would it present?

Answer 8

Hypercalcaemia due to PTHrP release:

• polydipsia + polyuria
• abdo. pain
• confusion + lethargy
• depression
• muscle weakness

Question 9

Which paraneoplastic syndromes are commonly associated with SCLC?

Answer 9

1. SIADH + hyponatraemia due to ADH release
   - N+V
   - muscle cramps + weakness
   - lethargy
   - seizures
2. Cushing’s syndrome due to ACTH-like peptide release
   - striae, hirsutism, acne
   - lethargy, depression, psychosis
   - muscle weakness
   - osteoporosis
   - central obesity + moon facies
   - HTN
3. Lambert-Eaton syndrome due to auto-Abs against VGCC
   - gradual proximal muscle weakness
   - autonomic Sx
   - reduced tendon reflexes

Question 10

Name 3 side-effects of cisplatin.

Answer 10

1. ototoxicity
2. peripheral neuropathy
3. hypomagnesaemia