Carcinoma of the breast: incidence, epidemiology, RFs

Question 1

1. how common is breast cancer?
2. how common in terms of mortality?
3. prevailing form of the cancer?
4. genetic subtypes most common?

Answer 1

1. most common non-skin malignancy in women
2. second only to lung cancer in death count
3. most are adenocarcinoma
4. HER-/ER+, HER-/ER-, HER+/ER(+/-): most are HER-/ER+

Question 2

1. Significance of benign epithelial changes:
2. nonproliferative changes
3. proliferative changes without atypia
4. proliferative changes with atypia

Answer 2

1. associated with invasive carcinoma
2. nonprolif changes do not increase risk of cancer
3. prolif changes without atypia increase risk 1.5-2x
4. prolif changes with atypia increase risk 4-5x

Question 3

age associations

Answer 3

rare before 25, rapidly increases after 30

Question 4

RFs:

1. hereditary
2. ethnicity
3. peak-age
4. menarche association
5. conception association
6. benign breast disease associations

Answer 4

1. First degree relatives with breast cancer increase the risk by 15-20%
2. Non-hispanic white women have the highest incidence in the US
3. Ashkenazi Jews have high BRCA1/BRCA2 rate
4. menarche before age 11 increases risk of breast cancer by 20%
5. peak of breast cancer between 70-80
6. conception before age 20 lowers a woman’s risk of BC by 50%
7. prolif changes and atypical hyperplasia increase risk of invasive carcinoma

Question 5

RFS

1. estrogen exposure
2. oophrectomy
3. breast density
4. radiation
5. carcinoma of contralateral breast or ovaries
6. obesity

Answer 5

1. menopausal estrogen hormone therapy increases risk
2. oral contraceptives do not increase risk
3. most “excess cancers” are small ER+ carcinomas
4. oophrectomy: reduces risk of developing breast cancer by 75% because it reduces estrogen exposure
5. breast density: very dense breasts increase risk 4-6 times
6. radiation increases
7. 1% increased risk of developing a 2nd carcinoma per year
8. obesity lowers risk because of anovulation–> reduces estrogen exposure

Question 6

major known susceptibility genes

Answer 6

BRCA1, BRCA2, TP53, CHEK2

Question 7

20-40% increase in ovarian cancers associated with what gene

Answer 7

BRCA1

Question 8

1. 10-20% increased risk for developing ovarian cancer associated with what gene?
2. which gene is most commonly associated with male breast cancer?
3. chrom 17
4. chrom 13
5. germline mutations

Answer 8

1. BRCA2: male breast cancer more commonly associated
2. BRCA2: less commonly associated with ovarian carcinoma as BRCA1
3. BRCA1
4. BRCA2
5. TP53 in li fraumeni syndrome, CHEK2,

Question 9

BRCA2 chromosome, associations

Answer 9

chrom 13, ashkenazi jews 1/40, more often ER+ than BRCA1, poorly differentiated carcinoma

Question 10

BRCA1 chromosome, associations

Answer 10

Chromosome 17, ashkenazi jew 1/40, more commonly poorly differentiated with “medullary features”