412 Obstetrics and Gynecology Board Review •••
❍ What is the risk of developing breast cancer for a person with LCIS?
These patients have a rate of development of invasive carcinoma of about 1% to 2% per year, with a lifetime risk of
30% to 40%.
❍ Is there an increased relative risk of development of invasive breast carcinoma in patients with sclerosing
adenosis?
1.5 to 2 times.
❍ What two genes account for the vast majority of inherited breast cancers?
BRCA1 and BRCA2.
❍ What percentage of breast cancer is genetic?
5% to 10%.
❍ Where are BRCA1 and 2 located?
BRCA1 is found on chromosome 17q21, and BRCA2 is found on chromosome 13q12.
❍ Is there a risk of development of other types of malignancies in patients with mutations involving BRCA1
and BRCA2?
Yes. BRCA1 mutations are associated with a pronounced increased risk of development of ovarian cancer (up to
60% by age 70), prostate cancer, and colon cancer. BRCA2 is associated with the development of male breast
cancer, ovarian cancer, and cancer of the bladder, prostate, and pancreas.
❍ What is the risk of development of breast cancer in a patient who has two first-degree relatives with breast
cancer?
4 to 6 times.
❍ Do the majority of women with a family history of breast cancer have the BRCA1 and 2 genes?
No, <10% do.
❍ How significant is the risk of development of breast cancer in a patient with Cowden disease?
These patients have up to 50% risk of development of breast carcinoma by the time they reach age 50.
❍ What initial receptors in carcinoma cells should be determined at the time of initial biopsy?
Estrogen, progesterone, and human epidermal growth factor receptor 2 (HER-2/neu).
❍ How common is the presence of estrogen receptors in carcinoma cells?
About half of the cases contain estrogen receptors.
❍ Why is it important to determine the presence or absence of estrogen and progesterone receptors in the
cytoplasm of tumor cells?
They are of proven value in determining adjuvant therapy and therapy for patients with advanced disease.