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 or Lambert Eaton syndrome

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.
Can secrete PTH causing hypercalcaemia

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.

Can cause gynaecomastia

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- Pancoast tumour)
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

Recurrent laryngeal nerve palsy= hoarse voice

Phrenic nerve palsy= SoB

SVC obstruction= facial swelling, difficulty breathing and distended neck veins

Horners syndrome= miosis, ptosis and anhidrosis (Pancoast tumour)

Limbic encephalitis= Due to small cell cancer causing antibodies production aimed at limbic system causing memory impairment, hallucinations and seizures

Question 9

What investigations would you do if you suspected lung ca?

Answer 9

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

Lab:
Sputum cytology (ca cells)

Imaging:
CXR
-unilateral pleural effusion
-hilar enlargement -visible lesion

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

Work out staging and grading

Small cell

• often metastases
• can respond to chemo and radiotherapy

Non small cell

• surgery
• radiotherapy

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.