11-25 L1 Genetics of Cancer

Question 1

What is the percentage of hereditary cancers related to inhertied predispsition?

Answer 1

10%

Question 2

Define

PM (Prophylactic mastectomy)

Answer 2

• removes most but not all breast tissue
• Sig reduces breast cancer risk in women with a family hx (90%, 14 yr follow up)

Question 3

Name 2 chemopreventions and there outcomes

Answer 3

• Tamoxifen
  
  • 60% reduction of breast cancer incidence in high-risk women
• Oral Contraceptives
  
  • In general population, OCs reduce risk of ovarian cnacer after 5 yrs cumulative use

Question 4

Define

Li-Fraumeni syndome

and

associated cancers

Answer 4

• rare syndorme caused by germline mutatoin in TP53 on chromosome 17
• Other: sarcoma, brain, adreoncortical, leukemia and many other tumor types

Question 5

Define

cowden syndrome

and

associated symptoms

Answer 5

• mutations in PTEN gene on chromosome 10
• Thyroid cancer, macrocephaly (small head) multiple hamartomas, breast friboadenomas, uterine, fibroids, skin growths, hermitte-duclos, vascular lesions

Question 6

Define

**Peutz-Jehgers **

• characteristics
• risk for maliganacies

Answer 6

• autosomal dominant
• STK11 gene on chromosome 18
• Characterized by gastrointestinal polyposis and muccocutaneous pigmentation
• Risk for malignancy: colorectal gastic pancreatic, breast, and ovarian cancers