Oncology Princples

Question 1

What are the three broad classifications of genetic mutations causing cancer?

Answer 1

Tumour Supressor
Proto- Oncogenes
DNA Repair

Question 2

What are tumour supressor genes?

Answer 2

Help reduce division of cells

Both need to be inactivated (recessive) can be germ line or acquired

E.g., P53 (involved in cell cycle regulation and maintains integrity)

Question 3

What are proto-onco genes?

Answer 3

Functions become enhanced in carcinogenesis
Usually encodes growth factors, growth factor receptors and transcription factors
Only requires one mutation

Eg RAS (encodes GProtein for cellular signal transduction)

Question 4

What are mutations of DNA repair?

Answer 4

Mutation of these accelerate mutations of tumour supressor and proto-oncogenes

Eg ATM gene (detects DNA damage, produces syndrome of ataxia telangiectasia)

Question 5

What are BRCA1/2 genes?

Answer 5

Tumour Supressor genes

Carriers have a 55-85% lifetime risk

40% increase of Ovarian with BRCA1

Increased incidence of male breast/prostate/pancreas

Question 6

What is the RB1 gene?

Answer 6

On chromosome 13 encoding a tumour Supressor gene
If both alleles are inactivated - Retinoblastoma

Question 7

What is the APC gene?

Answer 7

Tumour Supressor on chromosome 5

Associated with FAP

Question 8

What is the most important known carcinogen?

Answer 8

Smoking

Responsible for 90% of lung cancers

Synergistic effect on neoplasms caused by other things (e.g. alcohol)

Question 9

Name four cancers that alcohol is particularly implicated in

Answer 9

H and N
Oesophageal (particularly squamous)
Breast Cancer
HCC

Question 10

Diet can have a massive impact on the occurrence of Cancer. Give four cancers particularly related to obesity.

Answer 10

Endometrial
Post Menopausal Breast Cancer
Oesophageal Cancer
Colorectal

Question 11

How can Colon Cancer risk be reduced with diet?

Answer 11

High volumes of veg and fibre

Question 12

What is the relation of Salt Fish in terms of cancer?

Answer 12

Increased incidence of nasopharyngeal cancer

Question 13

What is the relation of Aflatoxin (found in corn, nuts, soybeans) and Cancer

Answer 13

Increased incidence of HCC

Question 14

Viral infections play a significant role in initiating carcinogenesis but do require other factors. Name three carcinogenic viral infections

Answer 14

HPV
Hep B and Hep C
EBV

Question 15

What two malignancies is EBV most associated with?

Answer 15

Hodgekins and burkitts lymphoma

Question 16

Name a carcinogenic bacterial infection

Answer 16

H.pylori
- gastric adenocarcinoma and a role in developing gastric lymphoma

Question 17

Name a carcinogenic parasitic infection

Answer 17

Schistosoma haematobium

Question 18

Name Three industrial exposures and their associated cancers

Answer 18

Wood dust and formaldehyde = cancer of nasal cavity, nasopharynx and leukaemia

Asbestos = lung, ovary and mesothelioma

Silica = lung

Question 19

What is neurofibromatoses

Answer 19

Increased neural tumours

Question 20

How does neurofibromatoses present (3)

Answer 20

Birth/early childhood

Multiple brown spots concentrated

Enlargement and deformity of bones and curvature

Question 21

Six hallmarks of cancer?

Answer 21

1. Sustaining proliferative signalling
2. Evading growth suppressors
3. Enabling replication immortality
4. Activating invasion and metastasis
5. Inducing angiogenesis
6. Resisting cell death

Question 22

Define tumour

Answer 22

Swelling of the part of the body without inflammation, caused by an abnormal growth or tissue (benign or malignant)

Question 23

What is a benign growth?

Answer 23

Non-cancerous growth

Question 24

Malignant growth?

Answer 24

Cancerous growth

Question 25

What is premalignant dysplasia ?

Answer 25

Increasing degree of disordered growth, is reversible

Question 26

Metaplasia?

Answer 26

Change of cells to form that does not normally occur in the tissue (differentiation)

Question 27

Stage vs grade?

Answer 27

Stage = size of a tumour how far it has spread

Grade = appearance of cells (differentiation)

Question 28

FNA is?

Answer 28

Fine needle aspiration biopsy

Question 29

What is a core biopsy

Answer 29

Ultrasound guides process, collects tissue

Question 30

Surgical biopsy?

Answer 30

Removes all or part of abnormality