Lung Cancer

Question 1

Describe the different classifications of lung cancer?

Answer 1

Small cell carcinomas:
-15% of all lung cancers

Non small cell carcinomas:

• 80% of all lung cancers
• 95% are bronchial
• Squamous cell (40%)
• Adenoma (40%)
• Large Cell (10%) (less differentiated forms of squamous cell and adenomas)

10 year survival rate for all lung cancer is 5.5%

Question 2

Describe some key features regarding small cell lung cancer?

Answer 2

These are very aggressive cancers with a poor prognosis: 70% present with disseminated disease with an average survival of 6-12 months.

20-30% arise from the neuroendocrine Kulchitsky cells

Are often centrally located.

Rapidly growing and therefore responsive to chemotherapy however they rapidly develop resistance.

May present with endocrine symptoms: SIADH or Cushings

Question 3

Describe the key features of squamous cell carcinoma?

Answer 3

Most associated with smoking.

More common in males.

Most resectable form of lung cancer.

Question 4

Describe the key features of adenocarcinoma?

Answer 4

Usually peripherally located

10% are EGFR (endothelial growth factor +ve) making them responsive to Tyrosine Kinase Inhibitors

2.5% are ALK +ve and are therefore more responsive to certain treatments.

Question 5

Describe the risk factors of developing lung cancers?

Answer 5

SMOKING and COPD
Occupation (asbestos, silica, chromium, arsenic, iron oxides and radiation)
FH
Age

Question 6

Outline the epidemiology of lung cancer in developed countries, incidence and yearly mortality.

Answer 6

39000 new cases each year
~30000 deaths a year

The most common cancer in men
Second most common cancer in women

Question 7

Outline the clinical presentation of lung ca?

Answer 7

Pulmonary:
Cough
Haemoptysis
Dysopnea
Pleuritic pain
Wheeze/stridor

General:
Wt loss 
Dysphagia
Fever 
Weakness 
Nausea and vomiting

Invasive:
Hoarsening voice (recurrent laryngeal nn)
Horner’s syndrome (meosis, partial ptosis, anhydriasis)
Back pain
Clubbing

Endocrine:
SIADH
Cushings
Hypercalcaemia following inappropriate secretion of PTH (occurs in squamous cell lung ca)

Question 8

Describe some of the symptoms from local manifestation of lung ca?

Answer 8

Pleuritic pain from invasion into the pleura.

Hilar tumours can involve the recurrent laryngeal nn causing hoarseness.

Pancos tumour may compress sympathetic chain and cause horners syndrome.

May compress the oesophagus causing dysphagia.

Question 9

What investigations would you do if you suspected lung ca?

Answer 9

Bloods:
FBC
U/E's if vomiting
LFTs
CRP

Lab:
Sputum cytology (ca cells)

Imaging:
CXR
Staging CT scan
PET scan

Invasive:
Bronchoscopy and biopsy (to establish histological diagnosis)
Percutaneous transthoracic needle biopsy for peripheral lesions.

Question 10

Outline the management of lung Ca?

Answer 10

Initially staging and working out histological subtype.

Staging is with TNM system.

Potentially curative treatment is with surgical resection with follow up radiotherapy +/- chemotherapy.

Surgical resection is an option for stage I and II lung ca*.

Radical radiotherapy is also an option for those that cannot have surgery.

Chemotherapy and specific medications are used in EGFR and ALK positive adenocarcinomas.

Question 11

What are the most common sites of metastasis in lung cancer?

Answer 11

• Other areas of the lung.
• Adrenal glands.
• Bone.
• Brain.
• Liver.