W12 L2 Fri genetic counseling for familial cancer

Question 1

Hereditary, familial, & sporadic cancer

Answer 1

• Hereditary – strongly acting single gene effect
• Familial – some inherited component, possibly polygenic
• Sporadic – mostly just chance and/or environmental

Question 2

Risk assessment for breast/ ovarian cancer

Answer 2

Family history of breast or ovarian cancer can be used to estimate:
* A person’s risk of developing these cancers
* The probability of having an inherited variant in a known cancer predisposing gene
-Note that a family can be high risk but the chance of harboring the gene is low

Question 3

Key factor associated with increased risk

Answer 3

Multiple relatives affected by breast (male or female) or ovarian cancer
* Young age at cancer diagnosis in relatives
* Relatives affected by both breast and ovarian cancer
* Relatives affected with bilateral breast cancer
* Ashkenazi Jewish ancestry.
* “Triple negative” (ER-PR-Her2-) breast cancer pathology

Question 4

Things for a genetic counsellor to think about - Risk Assessment

Answer 4

• What category of risk are this family?
• Which features make this family stand out?
• Would they would be eligible for funded testing? If so, who to test?
• If testing is appropriate, how would this would be facilitated?
• Whilst this is being decided, what can we say to the paitient?
• Would they be interested in privately funding testing

Question 5

Types of genetic testing For genetic couselling

Answer 5

• Mutation detection
  – Initially, it is performed in someone who is
  affected
  – A search for a mutation in a particular gene or
  set of genes
  – May or may not be present
• Predictive testing
  – Once a mutation (pathogenic variant) is found
  in a family, the family members can have
  “predictive testing” – testing for the specific
  variant that is has been identified in a family
  member

Question 6

Why would testing not be offered for a patient

Answer 6

An unaffected/undiagnosed person is not usually offered mutation detection because it may not differentiate between two outcomes:
1. There is a mutation but they haven’t inherited it
2. The cause of the family isn’t from a testable mutation

Question 7

Benefit of genetic testing

Answer 7

-decision making for the future
- offer test to other family member if mutation is found
- early monitoring and risk preventive action
- relive from possible cancer risk

Question 8

Risk of genetic counseling

Answer 8

-regret in knowing that they have the mutation
-anxiety about the future
-burden from family dynamic, possible pass on to the family
-genetic discrimination