Chapter 18: Breast and Axillae
1. A 44-year-old female mathematician presents to clinic with a complaint of a mass in the right breast. Her
partner noticed this mass 2 days ago, and the patient feels guilty because she has only had one mammogram
and does not engage in breast self-examination (BSE) on any regular basis. She has no family history of
breast cancer, and her prior mammogram was ordered as a routine screening test at age 43 years after a brief
discussion with her primary care provider. After a thorough investigation reveals a benign cyst, what advice
should be given to this patient about screening for breast cancer in her age group?
a. BSE is well evidenced, and all recommending agencies agree that it should be taught and reinforced.
b. Clinical breast examination (CBE) is superior to BSE and should be a routine part of annual examinations
starting at age 30 years.
c. This patient was in compliance with the U.S. Preventive Services Task Force (USPSTF)
recommendations for her age group and risk factors prior to her current complaint
d. Mammography is most sensitive and specific for women in their 40s, when breast tissue is still dense
enough to image accurately.
e. Breast cancer screening is extremely well studied, and no controversy exists on the recommended norms
for screening and follow-up.
Rationale: This patient was in compliance with the USPSTF recommendations for her age group and risk
factors prior to her current complaint. The USPSTF recommends that women age <50 years discuss risks
and benefits with their provider and decide on appropriate screening for their individual preferences and
needs. These recommendations are controversial and likely to change again over time, but they are
underpinned by one key issue: Mammograms have low sensitivity and specificity in younger women with
higher
2. A 42-year-old female website developer presents for an annual preventive examination with questions
about breast cancer screening. She is concerned about the radiation exposure associated with mammography
and is interested in magnetic resonance imaging (MRI) as a possible alternative for routine screening. She is
otherwise healthy with no family history of breast, ovarian, or colon cancer. Which of the following is true
about MRI as a screening modality for breast cancer in the general population?
a. Breast cancer screening by MRI has been well studied in the general population.
b. Sensitivity of screening for breast cancer increases with breast MRI at the expense of specificity.
c. This patient is an ideal candidate for screening via breast MRI based on current evidence
d. Women at low lifetime risk of breast cancer (<20%) are recommended to undergo screening MRI. e.
Known BRCA1 or BRCA2 mutation is insufficient criteria to justify screening with breast MRI. Rationale:
Sensitivity of screening for breast cancer increases with breast MRI at the expense of specificity. Increased
sensitivity (in this case, higher-resolution imaging to pick up subtler disease) is often traded for reduced
specificity (in the form of discovering many small items of no pathological significance). This is a core
concept in designing screening tests—very sensitive tests often pick up false positives, while very specific
tests often rule out disease effectively by missing many actual cases. Balance must be sought between these
two when setting thresholds for positive and negative screens. Breast cancer screening by MRI has been
well studied in the general population is incorrect. This screening modality has only been studied in high-
risk populations. This patient is an ideal candidate for screening via breast MRI based on current evidence is
incorrect. This patient meets no known criteria for screening with breast MRI (known BRCA mutation,
history of chest radiation, etc.). Women at low lifetime risk of breast cancer (<20%) are recommended to
undergo screening MRI is incorrect. Only women at high lifetime risk (>20%) are current recommended to
utilize breast MRI as a screening tool. Known BRCA1 or BRCA2 mutation is insufficient criteria to justify
screening with breast MRI is incorrect. The BRCA1 or BRCA2 mutation confers a risk >20% of breast
cancer over a lifetime, which is considered sufficient criteria for screening with MRI rather than
mammogram.
3. A 35-year-old G0P0 woman presents to clinic with a complaint of bilateral nipple discharge. This discharge
started several weeks ago and has occurred at irregular intervals since that time. She does not complain of local
tenderness, redness, fever, or any other systemic symptoms aside from slightly irregular periods over the last
