Mammography Flashcards
1
Q
Shape Lexicon BI-RADS
A
Descriptors of the mass shape
- Oval
- Round
- Irregular
2
Q
Evaluation of an ultrasound mass
A
- Look to the surrounding fat and not the surrounding fibroglandular tissue or generic surrounding tissue
3
Q
Indistinct Margins
A
- Can be related to the direct infiltration of tumor cells into the surrounding tissue
- However, non-malignant reasons for the indistinct margins include the host inflammatory/desmoplastic response to the tumor
4
Q
Clustered Microcysts
A
- Mammogram appearance of microlobulated margins. Isodense without visible fat.
- When comparing to the US think about the margins etc on the mammogram
5
Q
Wraparound Artifact on MRI
A
- A too small field of view will cause the overlap of the structures
- On T1 the appropriate field of view is approximately 320mm.
6
Q
Indistinct Margins
A
- Indistinct margins, no clear demarcations between mass edge and surrounding tissue.
- Can see on MR as a non-circumscribed enhancing mass
- This is always likely an an invasive ductal carcinoma
- Can also be invasive lobular cancers but statistically less likely.
7
Q
Anatomic zones in the breast
A
- Premammary
- Mammary
- Retromammary
- Anterior and posterior mammary fascia surround the mammary zone.
- Suspensory ligaments are formed by 2 leaflets of the mammary fascia
- Anterior suspensory ligaments are Cooper’s ligaments and connect to the dermis
- Connecting to the chest wall are the posterior ligaments
8
Q
Calcifications on BI-RADS
A
- BI-RADS 4 descriptors include amorphous and indistinct
- BI-RADS 5 descriptors include branching
9
Q
Molecular Breast Imaging/ Breast Specific Gamma Imaging
A
- Tc-99m is the radio-tracer
- Radiation critical organ is colon. Sestamibi is excreted through the biliary system can affect the colon from the radiation more than other structures.
- Any discrete lesion should eb onidered suspicion until proven benign by correlation with other breast imaging or biopsy
- Negative breast gamma imaging should not prevent biopsy of the suspicious lesions on conventional imaging
- Axillary lymph node uptake is common and benign if it corresponds to a mammographically stable node.
10
Q
Intraductal Papilloma
A
- US Imaging
- Isoechoic intraductal mass with internal vascular flow and adjacent fluid filled duct.
11
Q
Ductal Carcinoma in Situ (DCIS)
A
- Intraductal mass - less likely to present as a solid intraductal mass(compared to intraductal papilloma).
- ## Fine, linear, branching calcifications, confirming to ducal pattern. Can push it to BI-RADS 5. Can sometimes be BI-RADS 4C.
12
Q
Complicated Cyst
A
- Circumscribed margins, homogenous low-level echoes, posterior enhancement,
- Complicated because it contains internal echoes on ultrasound.
- US guided biopsy shows cyst wall wall and proteinaceous cyst contents.
13
Q
Margin Lexicon BI-RADS
A
- Spiculated
- Indistinct
- Obscured
14
Q
US Echogenic Halos
A
- Likely due to unresolved spiculations causing small reflections of the ultrasound beam
- Can also be secondary to peritumoral edema
15
Q
Regional vs Segmental calcification distribution
A
- Segmental - ductal distribution pattern with fine linear and branching morphology
- Regional - distribution would not have a clear ductal arrangement. - look like shards of glass rather than branching patterns
16
Q
US Physics
A
- Too narrow a dynamic range on US will cause a markedly hypoechoic lesion to appear anechoic.
- Too little gain would cause hypo echoic solid masses to be mistaken for cysts.
17
Q
US Evaluation of Internal Mammary Lymph Nodes
A
- Size is a better predictor of pathology than morphology.
18
Q
Lymphatic Drainage
A
- 75% of the lymphatic drainage of the breast is to the axillary lymph node.
- 25% of the drainage is primarily to the ipsilateral internal mammary chain lymph nodes
- A small amount of drainage may occur to the contralateral breast, skin, or internal mammary lymph nodes.
- Lymphatic drainage of malignancy may occur to the contralateral axilla or subdiaphragmatic lymphatics after disruption or obstruction of the ipsilateral lymphatic by tumor or post-treatment changes,.
19
Q
Pleomorphic Calcifications
A
- Broken shards of glass with calcifications of varying size and shapes that are typically more dense than amorphous calcifications.
- BI-RADS 4 regardless of the distribution of the calcifications.
20
Q
Associated with reduced sensitivity of the breast
A
- Very large breasts
- > 4cm in thickness
- Breast density does not alter sensitivity on US as it does on mammography
- Very large breast can have hard to detect small or deep mass 2/2 mobility of the breast and the higher frequency transducers used in evaluation for breast tissue.
21
Q
BI-RADS 3 Follow-up
A
- Surveillance is usually performed at 6 months, 12 months, and 24 months, with option to extend to 36 months if stable at each followup
- Amounts to a total of 3-4 Visits
22
Q
US guided wire localization
A
- The tip of the needle should be placed approximately 1.5-2 cm beyond (distal to) the center of the mass, which will allow the wire to be placed appropriately, with the tip of hook 2 cm from center of mass.
23
Q
Computer Aided Detection in Screening Mammography
A
- Sensitivity for calcifications is 86-99%
- CAD has one helpful mark per 2000-4000 false positive marks
- CAD is most sensitive for speculated masses
- Low CAD recognition for developing asymmetries
24
Q
BI-RADS 2 assessment for multiple similar circumscribed breast masses detected on screening
A
- BI-RADS 2 is validated for multiple bilateral breast masses with mostly (>75%) circumscribed partially obscured margins on mammography when there are at least 3 total similar findings with at least 1 in each breast.
- Not applicable with a dominant mass or suspicious features, and it excludes palpable masses.
