The Big 4 - Lung

Question 1

How common is lung cancer?

Answer 1

-Lifetime prevalence of 1 in 13 men / 1 in 15 women
10% 5YSR
-13% of all cancers
-21% of all cancer deaths
-Majority present with advanced disease

Question 2

What are the risk factors for lung cancer?

Answer 2

-Genetic predisposition
-Cigarette smoking
-Increasing age
-Hx of COPD
-Industrial exposure to asbestos, chromium, arsenic and iron oxide
-Radiation exposure

Question 3

What are the different histological types of lung cancer?

Answer 3

-Differentiated between small cell and non-small cell cancers

Question 4

What are the features of small cell lung cancer?

Answer 4

SMALL CELL (15%)
–highly aggressive, rapid growth, often metastasised and inoperable at point of diagnosis
–can respond to chemo at first but often relapse
–often associated with paraneoplastic syndromes eg SIADH, Cushing’s

Question 5

What are the features of non-small cell lung cancer?

Answer 5

3 main types of NSCLC (85%)
SQUAMOUS CELL CARCINOMA (30%)
–often found centrally, close to bronchi, can present with bronchial obstruction
–close link to cig smoking
–often causes clubbing
–secrete PTHrp –> hyperCa2+
ADENOCARCINOMA (50%)
–often peripheral
–more common in women, non-smokers and asbestos exposure
—EGFR and ALK mutations
LARGE CELL CARCINOMA (5%)
–less differentiated, metastasise early
Other types: carcinoid, mesothelioma, sarcoma, lymphoma

Question 6

How to patients present with lung cancer?

Answer 6

-Cough, dyspnoea, haemoptysis, chest pain, recurrent chest infections
-Specific site of tumour may produce more specific syndromes eg:
–apical tumour –> Horner’s syndrome / pain in nerve roots
–mediastinal invasion –> recurrent laryngeal nerve palsy, SVCO

Question 7

What investigations would someone with suspected lung cancer have?

Answer 7

-CXR
-CT chest + upper abdo – assess disease extent
-PET scan – if disease is operable to check for distant mets
-Bronchoscopy + biopsy (EBUS used to biopsy mediastinal lymph nodes)
-Tumour markers – LDH and NSE
-Lung Function – important for deciding fitness for treatment
-Cardiopulmonary exercise testing – important for deciding fitness for surgery

Question 8

How is SCLC managed?

Answer 8

CHEMOTHERAPY
-Considered a systemic disease so most given palliative chemo
-Very chemo-sensitive, so is the mainstay of management
-Can treat complications of disease eg SVCO
-Most will respond but also most will relapse (mets to brain is most common form of relapse)
RADIOTHERAPY
-Highly radio-sensitive
-Used to treat the primary tumour, prophylactically to prevent brain mets, palliatively
SURGERY
-Mostly inappropriate

Question 9

What is the prognosis of SCLC?

Answer 9

-Median survival = 2-4 months
-For those receiving chemo = 6-12 months
-10-15% survival in patients with good performance status, favourable biochemistry and limited disease

Question 10

How is NSCLC managed?

Answer 10

CHEMOTHERAPY
-Mostly used for those with metastatic / locally advanced disease
-Targeted therapy for those positive for mutations (EGFR+ALK)
-Immunotherapy eg pembrolizumab can be used also for those expression PDL1
RADIOTHERAPY
-Radical RT given to those with early stage disease and are unsuitable for surgery
-CHART used and given 3x a day for 12 days
-Also concurrent chemo-RT (later stage) and palliative RT given
SURGERY
-30% of NSCLC patients are suitable for surgery
-Resection has a good prognosis in early stage disease
-Adjuvant chemo given to those fit enough / with larger tumours

Question 11

What is the prognosis of NSCLC?

Answer 11

-3-6 months without treatment
-Increases to 1-2 years with chemo / immunotherapies