Lung Cancer

Question 1

What are the 2 categories of lung cancer?

Answer 1

non-small cell carcinoma (85%) and small cell carcinoma (15%)

Question 2

How can Non-small cell lung carcinomas be further classified?

Answer 2

Adenocarcinoma
Squamous cell carcinoma
Large cell carcinoma

Question 3

Describe the clinical features of adenocarcinomas of the lung.

Answer 3

More common in non-smokers and Asian females
Metastasise early

Responds well to immunotherapy

Question 4

Describe the clinical features of squamous cell carcinomas of the lung.

Answer 4

More common in smokers
Secrete PTHrP, causing hypercalcaemia

Metastasise late (via lymph nodes)

Question 5

Describe the clinical features of large cell carcinomas of the lung.

Answer 5

More common in smokers

Metastasise early

Question 6

Describe the clinical features of SCC of the lung.

Answer 6

More common in older smokers
Metastasise early

Secrete ACTH (Cushing’s syndrome) and ADH (SIADH)

Associated with Lambert-Eaton syndrome

Question 7

Describe the pathology of adenocarcinomas of the lung.

Answer 7

Located peripherally (in the smaller airways)

Question 8

Describe the pathology of squamous cell carcinomas of the lung.

Answer 8

Located centrally (in the bronchi)

Question 9

Describe the pathology of large cell carcinomas of the lung.

Answer 9

Located peripherally and centrally

Question 10

Describe the pathology of SSC of the lung.

Answer 10

Located centrally

Question 11

Describe the histology of adenocarcinomas of the lung.

Answer 11

Histology: glandular differentiation

Question 12

Describe the histology of squamous cell carcinomas of the lung.

Answer 12

Histology: squamous differentiation (keratinisation)

Question 13

Describe the histology of large cell carcinomas of the lung.

Answer 13

Histology: large and poorly-differentiated

Question 14

Describe the histology of SSC of the lung.

Answer 14

Histology: poorly-differentiated

Question 15

Name some risk factors of developing lung cancer.

Answer 15

The main risk factor is tobacco smoking, which is associated with 80% of lung cancer cases.

Other important risk factors include:

Air pollution (indoor and outdoor)
Family history of cancer, especially lung cancer
Male sex
Radon gas (typically affects miners)

Question 16

Name some typical symptoms of lung cancer.

Answer 16

Typical symptoms of lung cancer include:

Unexplained cough for at least 3 weeks (with or without haemoptysis)
Unintended weight loss (>5% in 6 months)
New-onset dyspnoea
Pleuritic chest pain (due to the tumour invading the pleura or the chest wall)8
Bone pain (due to metastases – commonly the spine, pelvis and long bones)9
Fatigue (due to anaemia of chronic disease)

Question 17

Name some typical clinical findings of lung cancer.

Answer 17

Cachexia: cancer can cause increased resting energy expenditure and lipolysis.12
Finger clubbing (Figure 1): the exact mechanism is unknown, but it may be due to increased secretion of growth factors, leading to the growth of the extracellular matrix in the nails.13
Dullness to percussion: due to the tumour (solids are less resonant than gases).
Cervical lymphadenopathy (Figure 2): due to metastasis to the lymphatic system.
Wheeze on auscultation: due to the tumour obstructing an airway.

Question 18

What are the NICE criteria for a 2WW referral for lung cancer?

Answer 18

Chest X-ray findings suggestive of lung cancer, or

Over 40 years old and unexplained haemoptysis

Question 19

Describe the criteria for sending patients for an urgent X-ray before a decision to refer via a 2WW.

Answer 19

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

Question 20

What is stage one of the TNM staging for lung caner?

Answer 20

One small tumour (<4cm) – localised to one lung

Question 21

What is stage two of the TNM staging for lung caner?

Answer 21

Larger tumour (>4cm) – may have spread to nearby lymph nodes

Question 22

What is stage three of the TNM staging for lung caner?

Answer 22

Tumour that has spread to contralateral lymph nodes, or grown into nearby structures (e.g. trachea)

Question 23

What is stage four of the TNM staging for lung caner?

Answer 23

Tumour that has spread to lymph nodes outside the chest, or other organs (e.g. liver)

Question 24

What is the appropriate management of stage 1-3 of NSC lung cancer?

Answer 24

Surgery: options include lobectomy/pneumonectomy in patients with intact lung function, or wedge resection in patients with reduced lung function (e.g. elderly, underlying respiratory conditions).

Pre-operative chemotherapy

Post-operative chemotherapy and radiotherapy: may not be needed in some cases of stage I lung cancer

Question 25

What is the appropriate management of stage 4 of NSC lung cancer?

Answer 25

Targeted therapy: these drugs target mutations which drive the pathogenesis of lung cancer (Table 3). Medical students should be aware that these targeted therapies exist and are used for stage IV lung cancer, but do not need to know much more detail than this.

Immunotherapy: these drugs target immune checkpoints, which prevent the patient’s immune cells from killing tumour cells. For example, the immune checkpoint PD-L1 is targeted by pembrolizumab. Immunotherapy is an emerging field in cancer management.

Chemotherapy: especially important for patients who do not have any mutations which can be targeted by targeted therapies.

Palliative care: includes palliative radiotherapy, for metastases and symptom control.

Question 26

Name a drug used in the management of NSC lung cancer with the EGFR mutation.

Answer 26

Gefitinib

Osimertinib

Question 27

Name a drug used in the management of NSC lung cancer with the ALK mutation.

Answer 27

Alectinib

Question 28

Name a drug used in the management of NSC lung cancer with the ROS1 mutation.

Answer 28

Crizotinib

Question 29

Name the management of small cell lung cancer.

Answer 29

Chemotherapy and radiotherapy

Surgery: rare in small cell lung cancer, as most patients present with advanced disease.

Prophylactic cranial irradiation: since small cell lung cancer is associated with a high risk of brain metastases, radiotherapy is directed at the brain to prevent brain metastases.

Question 30

Describe Horner’s syndrome.

Answer 30

Due to a Pancoast tumour in the lung apex infiltrating the brachial plexus. Features include ptosis, miosis, anhidrosis (reduced sweating) and enophthalmos (posterior displacement of the eyeball into the orbit).

Question 31

Describe superior vena cava obstruction.

Answer 31

tumour compresses the superior vena cava, preventing venous drainage from the head and neck, leading to facial swelling and distended neck/chest veins.

Question 32

Name 2 types of paraneoplastic syndromes.

Answer 32

SIADH and Lambert-Eaton syndrome.

Question 33

Name 3 treatment- related complications of chemotherapy.

Answer 33

alopecia, neutropaenia, bone marrow toxicity

Question 34

Name 3 treatment- related complications of radiotherapy.

Answer 34

mucositis, pneumonitis, oesophagitis