Breast imaging

Question 1

What does the breast lie over ?

Answer 1

2nd to the 6th ribs in the midclavicular line, anterior to the deep pectoral fascia and the lower part overlying the serratus anterior

Question 2

What is the layer of loose connective tissue between the breast & pectoral fascia called ?

Answer 2

The rectomammary space

Question 3

What is the breast enclosed in ?

Answer 3

In superficial fascia

Question 4

What are the 4 quadrants of the breast?

Answer 4

• Upper inner & upper outer
• Lowe inner & lower outer

Note - it also has an extension called the axillary tail of spence

Question 5

List some of the indications for breast imaging to be done

Answer 5

• Lumps including axillary ones (due to the axillary tail of spence)
• Unilateral nipple discharge or blood stained discharge
• Skin tethering or dimpling
• Signs of inflammation

NOT for pain, tenderness or symmetrical nodularity, only required for pain if there is associated asymmetrical nodularity

Question 6

What is the pathway for diagnosing breast lesions ?

Answer 6

Tripple assessment (clinical exam, imaging & pathology - histo & cytology)

Question 7

What are the 3 main imaging methods which can be used for assessing breast problems ?

Answer 7

1. Mammography (film/screen or digitial)
2. Ultrasound
3. MRI

Question 8

What determines which imaging modality is used for assessing a breast problem ?

Answer 8

There symptoms & age

• U/S is generally 1st line if they are < 40 (no radiation)
• Mammography +/- U/S is usually done otherwise

Question 9

Why is mammography (XRM) the method of choice for breast sceening ?

Answer 9

Because it is the only technique which readily visualises microcalcifications (<0.5mm) - microcalcifications accound for approx 30% of invasive cancers

Question 10

What is the main advantage of digitial XRM over film/screen XRM ?

Answer 10

It shows better contrast between dense & non-dense tissues ==> better in dense breasts & younger women

Question 11

What is the appearance of tissues on XRM?

Answer 11

• Fat tissue = low density (darker)
• Glandular tissue = higher density (whiter)
• Calcifications = bright white
• Lymph nodes: oval/horseshoe, fatty hilum

Question 12

Who are dense breasts more common in ?

Answer 12

Younger & thin women

Question 13

Taking what can slow down the decrease in breast density as a women ages ?

Answer 13

Taking HRT

Question 14

What are the features suggestive that calcifications seen are malignant ?

Answer 14

• Cluster or segmental distribution, if scattered or diffuse think benign
• Rhomboid shape of the cluster
• Spiculated shape (little branches coming off it) or linear jagged/irregular mass
• Pleomorphic nature (they vary in size, shape & density)

Question 15

What are the indications for using ultrasound when assessing breast problems ?

Answer 15

• Used to help characterise mammographic findings e.g. differentiation of cystic & solid lesions
• Palpable lesions < 40yrs old
• Nipple discharge
• Breast implants/augmentation
• Other inflammatory conditions (abscesses)
• Evaluation of response to chemo

Question 16

Describe the appearance of benign solid breast lesions on US

Answer 16

• Circumscribed - good borders
• Hypoechoic/hyperechoic
• “Wider than Tall”
• Homogeneous - lesions look similar
• Peripheral/no vascularity
• Often Multiple

Question 17

Describe the appearance of malignant solid breast lesions on US

Answer 17

• Poorly Circumscribed - bad borders
• Hypoechoic
• Heterogeneous
• “taller than wide”
• Spiculate
• Oedema/peritumoral fat

Question 18

What are the problems with XRM and U/S and hence why is MRI needed as a 3rd option ?

Answer 18

XRM:

• ↓sensitivity in dense breasts (≈55%)
• Observer limitations
• High % indeterminate lesions needing biopsy
• Compression
• Irradiation

U/S:

• Operator-dependent
• Time-consuming
• Reproducibility
• Misses calcifications
• Unproven in screening -false positives+++

Question 19

What are the benefits of MRI for imaging of breasts ?

Answer 19

• Excellent intrinsic tissue contrast
• No compression or irradiation
• Accuracy independent of breast density

Question 20

What are the signs of breast malignancy on MRI ?

Answer 20

• Ductal enhancement
• Rim enhancement
• Irregular mass
• Spiculated mass

Question 21

What are the contraindications to MRI ?

Answer 21

Absolute –as for any other MR exam:

• (cardiac pacemakers, ferromagnetic aneurysm clips, cochlear implants, renal impairment etc.)

Relative:

• pregnancy, lactation (effect of gadolinium based contrast, increased background breast enhancement

Question 22

What are the indications for the use of MRI in assessing breast problems ?

Answer 22

Benign disease:

• implants (integrity) - gold standard for this
• problem solving (lesion characterisation)

Malignant disease:

• diagnosis (occult 1° breast cancer)
• staging and treatment planning
• residual disease post WLE
• response assessment -chemotherapy
• recurrent disease –breast, reconstructed breast, axilla
• screening –high risk groups

Essentially MRI can help & is used to screen young very high risk women (BRCA & pT53 mutations) or implants, otherwise ask the radiologist

Occult primary tumors, or cancers of unknown primary (CUPs), are defined as histologically proven metastatic malignant tumors whose primary site cannot be identified during pretreatment evaluation.

Question 23

What are the problems with MRI use in breast problems ?

Answer 23

• Overdiagnosis
• Cost & Acess
• Patient tolerance (lots of people dont like MRI’s)

Question 24

What is the age women are screened for breast cancer ?

Answer 24

Between 50-70 (after 70 encouraged to make their own appointments)

Question 25

Are any women screened for breast cancer \< 50 yrs old ?

Answer 25

Yes - Women who are at an increased risk of breast cancer due to their family history may be offered screening from a younger age. The following patients should be referred to the breast clinic for further assessment: * one first-degree female relative diagnosed with breast cancer at younger than age 40 years * one first-degree male relative diagnosed with breast cancer at any age * one first-degree relative with bilateral breast cancer where the first primary was diagnosed at younger than age 50 years * two first-degree relatives, or one first-degree and one second-degree relative, diagnosed with breast cancer at any age * one first-degree or second-degree relative diagnosed with breast cancer at any age and one first-degree or second-degree relative diagnosed with ovarian cancer at any age (one of these should be a first-degree relative), or * three first-degree or second-degree relatives diagnosed with breast cancer at any age

Question 26

Who is MRI screening for breast cancer used for ?

Answer 26

High risk groups: 1. Previous irriadiation (e.g. hogkins lymphoma treated with mantle field XRT - chest exposed in this field) 2. BRCA 1/2 or TP53 mutations (Li Fraumeni) 3. Personal history of fam cancer (referring to the ones referred for assessment, some of these people may have this type of screening)