General pathology of cancer

Question 1

Predisposing factors for cancer

Answer 1

1. Hereditary
Germline
- Inherited mutations
- BRCA1/2
- APC gene
- HNPCC

2. Non-hereditary / Sporadic
   - Age
   - Environmental / geographical
   - Personal / lifestyle - smoking, obesity, sun exposure
   - Chronic inflammatory conditions: H. Pylori, IBD, Hep B
   - Carcinogens

Question 2

How is radiation carcinogenic?

Answer 2

• Skin cancers
• Formation of pyrimidine dimers in DNA which is normally repaired by NER, but not always. You will get unstable DNA which remains and divides…
• Causes mutations in oncogenes and TSGs

Question 3

Mechanism of action of Helicobacter pylori

Answer 3

• Gram negative with S-shaped appearance
• Present in 90% patients with chronic gastritis
• Adheres to epithelial cells to remain within mucus layer and produces urease, breaking down carbon dioxide to ammonia. Ammonia is toxic to epithelial cells, it can cause inflammation, ulcers, and potentially act as a carcinogen

Question 4

Malignant vs benign tumours

• Growth
• Borders
• Invasion
• Metastasis

Answer 4

Malignant:

1. Rapid growth
2. Ill defined borders
3. Infiltrative margins
4. Invades surrounding tissue
5. Ability to metastasise

Benign:

1. Slow growth
2. Localised
3. Expansile
4. Fibrous capsule
5. No capacity to metastasise

Question 5

Routes of metastasis

Answer 5

1. Lymphatic
2. Haematogenous
3. Transcoelomic: peritoneal/pleural cavities

Question 6

Definition of anaplasia

Answer 6

Condition of cells with poor cellular differentiation (maturation), losing morphological characteristics of mature cells and their orientation with respect to each other and endothelial cells

Question 7

What is Cachexia? Signs & symptoms

Answer 7

• Wasting syndrome
• Catabolic state resulting in profound loss of body fat and mass, weakness and anorexia
• Reduced food intake: alteration in taste, appetite control but high metabolic rate
• Due to molecules secreted by neoplasm and host response

Question 8

TNM tumour stage: what does each letter mean

Answer 8

1. T - Primary tumour: (T0-T4)
2. N - Lymph node status (N0-N3)
3. Metastasis (M0-M1)