Genetics Unit 22: Genetics Of Cancer 2

Front 1

Sporadic cancers

Back 1

Mutations that trigger tumorgenisis in somatic cells and therefore are not inherited. Acquired over a persons lifetime via carcinogens and such. Majority of cancers are these.

Front 2

Inherited Cancers

Back 2

Mutation present in germline results in inherited predisposition towards developing cancer. Cancer always occurs as a multistep genetic process.

Front 3

4 things which make one suspect hereditary cancer.

Back 3

1) Diagnosis before age 50
2) 2 or more primary cancer diagnoses in same individual
3) Multiple people in family with same or related tumors
4) Presence of physical features associated with an inherited cancer syndrome.

Front 4

2 major breast cancer genes and % that are genetic

Back 4

BRCA1 or 2.
5-10% genetic

Front 5

% chance of breast or ovarian cancer with BRCA1 mutation? BRCA2?

Back 5

BRCA1:
Breast = 50-85%
Ovarian = 40-50%
BRCA2:
Breast: = 50-85%
Ovarian = 10-20%

Front 6

Red flags for BRCA1/2 mutations

Back 6

1) Breast cancer diagnosis before age 50
2) Bilateral
3) Male breast cancer
4) personal/family history of ovarian cancer
5) Ashkenazi Jews (2% of women have mutation)

Front 7

Screening for breast cancer

Back 7

1) Monthly breast self exam
2) Clinical breast exam 2 times a year
3) Annual mammogram and breast MRI

Front 8

3 reasons why you dont do genetic tests on children (under 18) for adult on set disorders

Back 8

1) No risk for childhood malignancies
2) Would not change medical management
3) Takes away child's autonomy (they might not want to know)

Front 9

Cowden Syndrome

Back 9

Caused by a mutation in PTEN gene. Have 50% increased risk for breast cancer. Also increase in thyroid and uterine cancers. Also have:
-large head
-goiter
-skin probs
-intestinal polyps
-cognitive impairment

Front 10

Li-Fraumeni syndrome

Back 10

Caused by mutation in TP53. Increased risk for breast cancer, brain tumors, osteocarcenoma, and lots of others cancers. Lifetime cancer risk is 85-90%, 50% before the age of 40

Front 11

Lynch Syndrome

Back 11

Autosomal dominant disorder. 80% risk of colon cancer, typically before 50. Increased risk for endometrial, ovarian. Tumors usually in ascending colon and less polyps than standard colon cancer.
5 different mismatch repair genes can cause syndrome. MLH1 and MSH2 are most common.
90% have microsatellite instability (MSI).

Front 12

Familial Adenomatous polyposis (FAP)

Back 12

Mutation in APC gene. Autosomal dominant. Precancerous polyps develop at 16. Hundreds of them. 1005 risk of colon cancer if colonectomy isnt performed. Also at risk for upper gi and liver cancers as well as thyroid.
Retinal pigmentation can be diagnostic.
Genetic testing of children is appropriate.

Front 13

Genetic information non-discrimination act (GINA)

Back 13

Prohibits health insurance and employment discrimination based on genetic information or test results. Does not protect against discrimination in life insurance, disability, or long term care insurance.