Lecture 19

Question 1

Breast & Ovarian Cancer Genetics & Breakdown

Answer 1

• BRCA1 & 2
• Autosomal Dominant

Breast Cancer
Sporadic - 70-80%
Familial - 15-20%
Hereditary 5-10%

Ovarian Cancer
Sporadic 75-90%
Hereditary 10-25%

Question 2

Increased Cancer Risks of BRCA1&2

Answer 2

Breast, Ovarian, Pancreatic, Prostate, Melanoma

Question 3

Indications for BRCA1 Testing

Answer 3

o Personal hx of pancreatic cancer, pathogenic BRCA mutations were identified in 4.6% of a large cohort of clinic-based patients
o Somatic brca1/2 pathogenic variant; 2.3% patients had previously unrecognized pathogenic germline mutations in 19 cancer-related genes
o Genomic sequencing must be accompanied by a plan for return of germline results, in partnership w/ genetic counseling

Question 4

CHEK2

Answer 4

o	Moderate risk
o	Autosomal dominant
o	Increased cancer risks
	Breast 23-48%
	Colon
	Prostate
	Thyroid
	Endometrial
	Ovarian

Question 5

ATM

Answer 5

o	Moderate risk
o	Autosomal dominant
o	Increased cancer risks
	Breast 17-60%
	Prostate
	Pancreatic

Question 6

NBN

Answer 6

o	Autosomal dominant
o	Homozygous mutation Nijmegen Breakage syndrome
o	Increased cancer risks
	Breast 23-48%
	Melanoma
	Non-hodgkin lymphoma

Question 7

Important Family History

Answer 7

o	Cancer
	Age of onset
	Type
	Pathology
o	Genetic testing
o	Surgeries
	Breast, ovaries

Question 8

Important Points

Answer 8

• Advancements of genetic testing for hereditary cancer
o Better understanding of genes and mutations
o Testing technology/detectable mutations
• Multigene testing is ideally offered in context of pre-/post-test genetic counseling
• High, moderate, and newer risk hereditary cancer genesvarious syndromes and cancer risks
• Genetics testing is complex – partner w/ a genetics professional
• Every patient’s experience is different from testing to risk management