6- Resp Pathology

Question 1

What are 6 clinical features of lung cancer

Answer 1

Cough 
Chest/Shoulder pain 
Chest signs 
Dyspnoea 
Hoarseness
Finger clubbing

Question 2

Describe TNM staging

Answer 2

If the tumour is closer to the mediastinum or the chest wall then it has a HIGHER T STAGING irrespective of its size
• So you T staging is based on location, size and proximity to other organs
• If the tumour spreads to the lymph nodes in the neck then there is higher staging

Question 3

Describe how PEt scans are used

Answer 3

Patients fast for 4 hours and are then given radiolabelled glucose
• The lung as a whole is not very active but the tumour is very metabolically
active and hence show up very clearly

Question 4

How does small cell and non small cells lung cancer treatments differ

Answer 4

Small Cell Lung cancer usually grows rapidly and metastasise early - treatment involves chemotherapy and radiotherapy

If it is localised, then the best treatment is surgery
• 5 year survival is around 70%
If there is advanced disease with lymph node involvement you’d give chemotherapy to begin with to try and reduce the extent of the spread

Question 5

What are the 4 types of malignant epithelial lung tumour

Answer 5

Non-small cell carcinoma has THREE types:
• Squamous Cell Carcinoma (20-40%)
• Adenocarcinoma (20-40%)
• Large Cell Carcinoma (uncommon)

• Small Cell Carcinoma (20%)
• Much worse prognosis than non-small cell
• It is unusual to find an early stage small cell carcinoma because they
grow rapidly and metastasise early

Question 6

What is the most common type of cancer among non smokers

Answer 6

Adenocarcinoma

Question 7

How does a carcinoma develop

Answer 7

Metaplasia

2. Dysplasia
3. Carcinoma in situ
4. Invasive carcinoma

Question 8

Describe squamous cell carcinoma

Answer 8

Squamous cell carcinoma tends to arise in the airways
• The airway epithelium reacts to the chronic irritation of cigarette smoke - the epithelium changes to a TOUGHER squamous epithelium
Accounts for 25-40% of lung cancer

Question 9

Describe adenocarcinomas

Answer 9

Forms from glandular epithelium
• Tend to develop in the periphery and are increasing in incidence because of deeper inhalation of cigarette smoke and because it is more common in non- smokers
25-40% of lung cancer

Question 10

What are the 2 molecular pathways associated with adenocarcinoma and why is this significant

Answer 10

Smoker = K ras mutation (DNA methylation + p53)
• Non-Smoker = EGFR mutation/amplification (Epidermal Growth
Factor Receptor)

• If the patient has a K ras mutation then they ARE NOT going to respond to targeted therapy (like Tarceva)

Question 11

Describe large cell carcinoma

Answer 11

Poorly differentiated tumours composed of LARGE
cells
• NO histological evidence of glandular or squamous
differentiation

Question 12

Describe small cell carcinoma

Answer 12

Cells are small with basically just nuclei
20-25% of all lung cancer
• Often central near the bronchi
• Very close association with SMOKING
• 80% of cases present with advanced disease
• Although very chemosensitive - there is an awful
prognosis

Question 13

What is Mesothelioma

Answer 13

Malignant pleural tumour due to asbestos exposure, essentially fatal

Question 14

What is the 5 year survival rate of lung cancer

Answer 14

Less than 6%

Question 15

What is a paraneoplastic syndrome and give examples

Answer 15

Paraneoplastic Syndrome = systemic effect of tumour due to abnormal expression by tumour cells of factors (e.g. hormones) NOT normally expressed by the tissue from which the tumour arose

Anti-diuretic hormone (ADH)
• You can get syndrome of inappropriate ADH (SIADH) causing
hyponatremia (especially in small cell carcinoma)
• Adrenocorticotropic Hormone (ACTH)
• Cushing’s Syndrome (especially in small cell carcinoma)