L22 Genetic Counselling

Question 1

FCC

Answer 1

Familial cancer centre

Question 2

Genetic Risk assessment

Answer 2

• Interpretation of family and medical histories to assess the chance of disease occurrence or recurrence
• Facilitation of genetic testing as appropriate

Question 3

Provision of information and advice

Answer 3

• education about inheritance, testing, management, prevention, resources and research
• cancer risk management and risk reduction advice

Question 4

Counselling

Answer 4

• promote informed choices and adaptation to the risk or condition
• assess client’s own perception and interpretation of family history
• explore client’s response to the information
• psychosocial support and reassurance

Question 5

Ongoing

Answer 5

• facilitation of family communication

- support for gene carriers

Question 6

Most cancers are not inherited but all are genetic

Answer 6

• most cancers caused by accumulation of mutations in specific cells that alter growth/inhibit normal apoptosis and allow cells to spread uncontrollable
• mutations are somatic not germline

Question 7

How cancer develops

Answer 7

see onenote

cancer tends to involve multiple mutations

Question 8

Hereditary, familial and sporadic cancer

Answer 8

Hereditary - strongly acting single gene effect

Familial - some inherited component, possibly polygenic

Sporadic - mostly chance and/or environmental

Question 9

Definitions of types of cancer

Answer 9

see onenote

Question 10

Common forms of hereditary cancer

Answer 10

see onenote

e.g. hereditary breast and ovarian cancer, lynch syndrome, familial adenomatous polyposis (APC)

Question 11

Risk assessment for breast/ovarian cancer

Answer 11

see onenote

Family history of breast/ovarian cancer can be used to estimate:

• person’s risk of developing these cancers
• probability of having an inherited mutation in a known cancer predisposing gene

Question 12

Risk assessment and management guidelines

Answer 12

see onenote

Question 13

What happens when a patient is referred to the FCC?

Answer 13

see onenote

Question 14

Case study

Answer 14

see onenote

Question 15

Things for a genetic counsellor to think about - risk assessment

Answer 15

see onenote

Question 16

Assessment for genetic testing

Answer 16

see onenote

Likelihood of known gene mutation
- BOADICEA score

Pathology
Limited Family History
Other cancers
Ancestry

Question 17

Risk assessment tools - BOADICEA

Answer 17

see onenote

Question 18

Verification of cancers in families

Answer 18

see onenote slides

Send entire family tree to cancer council in Victoria
- Looks up everyone on
pedigree to give additional information

Cancer not reported but was verified to have cancer by the council (the relatives themselves didn’t know another family member had cancer) => changes BOADICEA calculations as new information was acquired

Question 19

Types of genetic testing

Answer 19

see onenote

Mutation detection
Predictive testing

Question 20

New BOADICEA

Answer 20

see onenote

Question 21

Methods used for mutation detection

Answer 21

• next gen sequencing, also called massively parallel sequencing, to look at many genes at once
• sequencing = looking through the sequence to find small DNA changes or small indels
• can detect minor sequence variations as well as deletions/duplications

Question 22

Generalised benefits of genetic testing

Answer 22

see onenote

6 points

Question 23

Generalised risk of genetic testing

Answer 23

see onenote

11 points

Question 24

Genetic testing process - practicalities

Answer 24

see onenote

blood sample and consent required from living affected individual

mutation detection
- performed using targeted gene panel

genetic counselling

• informed consent
• pros and cons

Question 25

Outcomes of genetic testing

Answer 25

see onenote

1. pathogenic mutation found
2. likely pathogenic mutation found
3. variant of unknown/uncertain significance
4. polymorphism
5. no mutation

Question 26

Mutation identified in Annette - predictive testing available for family members

Answer 26

see onenote

Question 27

Predictive testing

Answer 27

see onenote

For the genetic counsellor: what are some of the things she needs to think about?

e.g. insurance issues, possibility of passing on to children

Question 28

Cancer risks for BRCA1 carrier

Answer 28

see onenote

Question 29

Risk management strategies

Answer 29

see onenote

1. surgical
2. surveillance
3. risk reducing medications

Question 30

Some more issues to think about

Answer 30

see onenote

having kids tested, ethical issues associated with this

Question 31

More genes associated with cancer risk

Answer 31

see onenote

Personalised medicine
- Everyone could get their risk profile; do they carry common but low risk alleles

Question 32

Actionable incidental findings are common

Answer 32

see onenote

Question 33

Rare cancer syndromes

Answer 33

see onenote

Question 34

Hereditary diffuse gastric cancer

Answer 34

see onenote slides

• autosomal dominant
• gene: CDH1 (E-cadherin)
• majority of CDH1 related cancers occur before 40