Lung Cancer

Question 1

Types of Lung Cancers

Answer 1

Small Cell Lung Cancer
Non-small Cell Lung Cancer

Question 2

Define small cell lung cancer

Answer 2

• aggressive malignant epithelial cell tumour primarily in older smokers.
• neuroendocrine carcinoma as the cells contain neurosecretory granules that release neuroendocrine hormones

Question 3

Pathophysiology of small-cell lung cancer

Answer 3

accumulation of driver mutations causing benign progenitor cells to transform into neoplastic cells.
can cause paraneoplastic syndrome because the cells release neuroendocrine hormones
- i.e. if releasing ADH, can cause hyponatraemia.

Question 4

where do SCLC typically arise from?

Answer 4

in central lung with mediastinal involvement, typically disseminated at time of diagnosis due to early metastasis

Question 5

what percentage of Lung Cancers are SCLC?

Answer 5

15-20%

Question 6

symptoms of lung cancer

Answer 6

cough
chest pain
haemoptysis
dyspnoea
weight loss
hoarseness
back pain

Question 7

signs of lung cancer

Answer 7

lymphadenopathy
stridor, wheeze = obstruction
fever
clubbing
signs of pleural effusion
hypertrophic pulmonary osteoarthropathy
phrenic palsy -> hemidiaphragm paradoxical rise on sniffing

Question 8

What is hypertrophic pulmonary osteoarthropathy?

Answer 8

refers to a fibrovascular proliferation that results in periostitis of the long bones, arthralgia and clubbing. It is almost always secondary to another condition and there are many causes aside from lung cancer.

Question 9

Complications of SCLC (3)

Answer 9

paraneoplastic syndrome
obstruction and mucus -> giving wheeze
invasion and compression of mediastinal structures i.e., SVC obstruction; phrenic n. invasion; dysphagia; vertebral body erosion; pleural and pericardial effusions.

Question 10

differentials for SCLC

Answer 10

non-small cell lung cancer
pneumonia/bronchitis
carcinoid tumour

Question 11

Investigations for SCLC

Answer 11

first line: CXR
- central/peripheral mass
- lymphadenopathy in hilum or superior mediastinum
- pleural effusion
- broadening of mediastinum
- enlarged heart shadow

CT chest, liver, adrenal glands (mets)

CT for presence of lesion, staging, background changes (COPD)

Bronchoscopy

Biopsy

Question 12

Management for SCLC

Answer 12

Chemotherapy

Radiotherapy

Immunotherapy

Radio-chemotherapy in limited stage disease

Responds well initially but relapses
Active treatment achieves around 6 month increase in overall survival time

Question 13

Types of NSCLC

Answer 13

adenocarcinomas (most common - 40%)
squamous cell carcinomas (20%)
large cell carcinomas

Question 14

features of lung adenocarcinoma

Answer 14

• preceded by atypical adenomatous hyperplasia
• commonly in peripheries
• smaller than other types
• EGFR mutations, increased frequency in non-smokers, suitable for TRK inhibitors
• KRAS mutations
• Gynaecomastia

Question 15

features of lung squamous cell carcinoma

Answer 15

• preceded by squamous metaplasia, dysplasia, SCC in situ
• PTHrP -> hypercalcaemia
• increasingly seen in periphery -> can cause cavitation (differential for TB, lung abscess): exophytic ulcerates, bleeds -> early presentation
  endophytic infiltrates airways -> presents late

Question 16

what is bronchial carcinoids

Answer 16

5% of lung cancers
unrelated to smoking
in young adults
excellent prognosis

Question 17

Lung cancer on CXR

Answer 17

unilateral hilar enlargement
peripheral pulmonary opacities
lung, lobe, or segmental collapse
pleural effusion
broadening of mediastinum, enlarged cardiac shadow, elevation of hemidiaphragm
rib destruction

Question 18

targeted treatments for lung cancer

Answer 18

program death ligand 1 (PD-L1) inhibitor
tyrosine kinase inhibitors if EGFR mutated
cryzotininb for ALK and ROS translocations tumours