Mammography Flashcards
goal of screening mammography
detect pre-clinical breast cancer in asymptomatic women
ACR 2010 guidelines for screening mammography
annual screening > 40
screening 10 years younger than 1st degree relative with breast cancer
USPSTF recommendation for screening (2009)
class C: based on individual recommendations for women 40-49
recommend biannual screening for women 50-74
2 standard mammographic views
CC and MLO (45-60 degres from axial plane; parallel to pectoralis muscle heading into axilla
additional mammogram views technologists can obtain at their discretion
cleavage view (CV): medial breast tissue of both breasts
exaggerated CC (XCC): pulls lateral/medial tissue into image detector
online vs offline screening
offline: batch of exams reviewed in bulk, some time after films taken
online: mammography read while patients wait; typically leads to more imaging and false positives (same cancer detection rate)
is diagnostic radiology online or offline?
online
reasons for diagnostic mammography
breast problem (pain, lump, skin thickening, nipple discharge)
annual mammography in a asymptomatic pt with hx of breast cancer
short interval follow-up (BiRADS3)
evaluation of abnormality found on screening
diagnostic mammography steps
- localize mammographic abnormality in 3D
- US?
- pt waits until getting final interpreations/recommendations
technically adequate mammogram
- nipple in profile on at least one view
- MLO posterior nipple line to pectoralis muscle or edge of film on CC muscle
- posterior nipple lines on CC/MLO should be within 1 cm of each other
- no blur/artifacts
approach to mammography
- evaluate adequacy
- compare each side/symmetry
- evaluate for malignancy (mass, calcification, architectural distortion, asymmetry) and magnifcy
- compare to priors
BIRADS structure
- history/indication with risk factors stated
- list of comparisons
- description of breast composition
- description of significant findings/location
- BIRADS assessment and course of action
Types of breast composition
The breast is almost entirely fat (<25% glandular).
There are scattered fibroglandular densities (approximately 25%–50% glandular).
The breast tissue is heterogeneously dense, which could obscure detection of small masses (approximately 51%–75% glandular).
The breast tissue is extremely dense. This may lower the sensitivity of mammography (>75% glandular).
BiRADS 0
needs additional imaging; only for screening
such as spot compression, magnification, special mammographic views, or ultrasound) and/or prior mammograms are necessary before a final assessment can be assigned
BiRADS 1
negative
normal breasts. NO findings
BiRADS 2
benign findings. no work-up
BiRADS 3
probably benign, short interval follow-up recommended
<2% risk of malignancy
t is necessary to conduct a complete diagnostic imaging evaluation using diagnostic views (e.g., spot compression magnification, etc.) and/or ultrasound before assigning a probably benign (Category 3) assessment. Category 3 is never appropriate for screening mammography.
• According to the 4th Edition of BI-RADS (2003), Category 3 is not for palpable lesions. However, more recent data suggest that it is acceptable to assign appropriate palpable lesions as BI-RADS 3 after a full imaging workup.
• Action required: Short interval follow-up, typically 6 months. In general, if a benign- appearing lesion demonstrates 2 years of stability it can be considered benign (BI- RADS 2). Any interval change is suspicious and may warrant biopsy
follow-up recommendation for BiRADS 3
short interval follow up 6 monts ; if benign and demonstrates 2 years of stability, consider benign (BIRADS 2); interval change –> biopsy
BIRADS 4
suspicious of malignancy: 2-95% chance
can be subdivided into 4A-C
follow-up recommendation for BiRADS 4
biopsy/aspiration
BIRADS 5
highly suggestive of malignancy – biopsy or direct surgical treatment recommended
follow-up recommendation for BiRADS 5
biopsy/surgery
BIRADS 6
proven malignancy; identified lesion on prior biopsy
causes for unilateral increase in fibroglandular density
lymphatic obstruction
cause for bilateral increase in fibroglandular density
hormones/breast edema; pregnancy/lactation/weight loss
causes for bilateral trabecular blurring/skin thickening
CHF
benign causes of skin thickening
radiation, acute mastitis, CHF, renal failure, liver failure
malignant causes of skin thickening
inflammatory carcinoma, locally advanced carcinoma, lymphatic obstruction
