|
|
|
|
|
|
|
|
Assessing Family History
|
Hallmarks of Hereditary Cancer:
- 2 or more closely related family members, on one side of the family, with the same type of cancer
- a pattern of cancer over at least 2 generations
- cancers diagnosed at an earlier age than expected in the general population
- multiple primary cancers in 1 individual
- combinations of cancers associated with a known hereditary syndrome (e.g. breast and ovary; colon and uterine)
- specific pathology types (e.g. serous ovarian cancer)
See sample family histories below, and the interpretation provided.
Breast cancer is used in these examples, but the same principles apply to other types of cancer.
Key: circle=woman, square=man, filled in= type of cancer & age at diagnosis
Sporadic Cancer = single occurrence in a family
|
 |
- 70-75% of family histories
- majority of cancer cases
- diagnosis at typical ages
- related to common risk factors like age, diet, environment
- inherited risk unlikely
Genetics consult not indicated
|
Familial/Multifactorial Cancer = cluster of cancer within family
|
 |
- 20-25% of family histories
- 2 or more close relatives with cancer
- diagnosis at typical ages
- may be due to chance alone
- may reflect combination of shared environmental and moderate genetic risk factors
Genetics consult not indicated
|
Hereditary Cancer = inherited cancer predisposition
|
 |
- 5 - 10% of all cancers
- younger ages at diagnosis
- individuals may have multiple primary cancer diagnoses
- autosomal dominant inheritance - pattern over generations
Referral to Hereditary Cancer Program is indicated (see referral criteria).
- refer affected family member first if possible
- genetic testing may be available
| Return to top of page
|
|
|