Breast

Question 1

List the vessels responsible for artery supply of the breast

Answer 1

• internal thoracic artery, via the medial mammary and anterior intercostal branches;
• lateral thoracic and thoracoacromial arteries; and
• posterior intercostal arteries.

Question 2

List the vessels responsible for venous drainage of the breast

Answer 2

• mainly to the axillary vein via the lateral thoracic and lateral mammary veins; and
• also the internal thoracic and medial mammary veins.

Question 3

List the pathways of lymphatic drainage of the breast.

Answer 3

• from the nipple, areola and lobules of the gland to the subareolar complex;
• then, most to the axillary lymph nodes;
• some medially to the parasternal nodes or to the opposite breast; and
• some, especially from the lower quadrants of the breast, to the inferior phrenic nodes.

Question 4

Describe the normal u/s appearance of glandular tissue/parenchyma

Answer 4

• Glandular tissue/parenchyma: usually homogeneously echogenic; some hypoechoic areas within may represent ducts or fat lobules.

Question 5

Describe the normal u/s appearance of subcutaneous fat/fat lobules

Answer 5

• Subcutaneous fat/fat lobules: hypoechoic compared to the glandular tissue. Some striationsmay be seen within. Fat lobules are usually round but may have a variable shape. Subcutaneous fatlobules are usually larger than those in the retromammary layer.

Question 6

Describe the normal u/s appearance of pectoral muscles

Answer 6

• Pectoral muscle: hypoechoic with striations.

Question 7

Describe the normal u/s appearance of the retroareola region

Answer 7

• The retro-areolar region: some shadowing from the nipple may be noted; often hypoechoicducts may be seen terminating under the nipple.

Question 8

Describe the normal u/s appearance of Cooper’s ligaments

Answer 8

thin, echogenic lines, may not always be seen as this depends on their angle relative to the probe. They may be seen extending from the glandular tissue to the superficiallayer of the superficial fascia.

Question 9

Describe the normal u/s appearance of the skin

Answer 9

two thin echogenic lines either side of a hypoechoic band; may be thicker inferiorly in the breast at the inframammary fold, but is usually approximately 2mm in thickness.

Question 10

Describe a ‘TDLU’ and discuss why it is important.

Answer 10

A TDLU is a terminal duct lobular unit. This is the secreting unit of the breast, containing the terminal duct and mammary lobule (oval structures composed of acini or small ductules). During pregnancy they expand and secrete milk. The milk/secretions are then delivered into the larger duct system from the TDLU to the interlobular or segmental duct, then to the lactiferous sinus and then collecting duct at the nipple. The TDLU is important because many benign and malignant lesions can arise within it. These include cysts, adenosis, hyperplasia, fibroadenoma and most carcinomas.

Question 11

A) If a lesion is in the lateral portion of the breast in the CC and lies at the level of the nipple in the MLO, where should it actually lie in the breast?

Answer 11

Lower lateral quadrant, lateral lesions are projected higher on the MLO.

Question 12

B) If a lesion is in the medial portion of the breast in the CC and in the mid part of the breast in the MLO, where should it actually lie in the breast?

Answer 12

Upper medial quadrant, medial lesions are projected lower on the MLO.

Question 13

C) If a lesion is in the central portion of the breast in the CC and in the mid part of the breast in the MLO, where should it actually lie in the breast?

Answer 13

In the upper breast around 12 o’clock.

Question 14

D) If a lesion is not seen in the CC and lies high in the superior part of the breast in the MLO, where could it actually lie in the breast?

Answer 14

It is most likely to be actually in the axilla or the axillary tail. If it was lower in the MLO, it could lie in the supero-medial portion of the breast

Question 15

Describe the width X depth ratio and its significance.

Answer 15

The width X depth ratio is one of the many characteristics used in describing breast lesions in an effort to try to determine the potential malignancy of the lesion.
Lesions that are wider than they are high are more likely to be benign than those lying more upright (when scanning in the supine position). Therefore, a high ratio suggests a likely benign lesion, whilst a low ratio suggests malignant potential.
This type of shape suggests lesion growth that is across normal tissue planes and indicates malignant potential. Fibroadenomas usually grow within the tissue planes, flattening with the pressure of the fascial planes. Some cysts, though, may be very round. Therefore, the ratio should be used in combination with the other ultrasound characteristics when assessing a breast lesion.

Question 16

List the ultrasound characteristics you would most likely find in benign lesions.

Answer 16

Likely benign characteristics
• shape – round, oval , eliptoid
• texture - homogeneous
• echogenicity - anechoic, hyperechoic
• internal contents – solid, cystic
• presence of calcifications - only if large and smooth
• margin definition - smooth, macro-lobulations, sharp, thin halo or capsule
• posterior sound transmission - enhancement, shadow, no change
• orientation to skin – parallel to skin, along skin planes
• width X depth ratio - wider than tall
• mobile, compressible
• no architectural distortion /Cooper’s ligament distortion
• no disruption to superficial or deep fatty and fascial layers
• no nipple inversion/retraction
• no abnormal axillary lymphadenopathy

Question 17

List the ultrasound characteristics you would most likely find in malignant lesions.

Answer 17

• shape – round, irregular
• textures – heterogeneous
• echogenicity - hypoechoic
• internal contents – solid, mixed
• presence of calcifications – fine
• margin definition- irregular, spiculated, ill-defined, micro-lobulations, thick, irregular capsule
• posterior sound transmission - shadowing , no change
• orientation to skin, more upright
• width X depth ratio – low, more round or upright shape
• immobile, non-compressible, hard, irregular
• architectural distortion /Cooper’s ligament distortion
• disruption to superficial or deep fatty and fascial layers
• recent nipple inversion/retraction
• abnormal axillary lymphadenopathy

Question 18

Discuss the pathophysiology of fibrocystic breast change and describe the common ultrasound appearances.

Answer 18

Fibrocystic disease in the breast is a reactive and degenerative change, partially due to the consequences of hormonal stimulation and the breast’s reaction to this, and partially due to the consequences of aging. It does not usually occur prior to puberty and any symptoms gradually improve post-menopause. Usually both breasts are affected, but there is often asymmetry. Lumps are often easily palpable and often fluctuate in size. The breasts may have a nodular feel and are usually very tender, especially premenstrually.

The normal breast tissue responds to variations in hormone levels throughout the menstrual cycle in regard to proliferation and accumulating fluid. The breast undergoing fibrocystic change does so in a hyperplastic reactive and degenerative way. The typical features of fibrocystic change include epithelial proliferation, fibrosis and cysts. A less common feature is intraductal papillomatosis. Fibrosis occurs when the loose intralobular connective tissue is replaced with dense connective tissue. The ductal epithelium proliferates, ducts dilate and become trapped by these dense connective tissue strands, leading to cyst formation. The fibrous strands also undergo degenerative change due to interruption of blood flow, presenting eventually as stromal calcification. Epithelial proliferation occurs in the form of ductal budding and crowding – sclerosing adenosis. Some breasts develop intraductal cell proliferation and may grow small intraductal papillomas (these have some malignant potential).

Common ultrasound appearances of fibrocystic change
Cysts
• Simple cysts
• echo-free contents
• round/oval (round cysts may be under tension more than flaccid/flattened cysts)
• posterior enhancement
• smooth/thin walls
• edge refraction; reverberation artefacts within are common
• usually compressible and may feel mobile

Complex cysts
• septations/lobulations
• debris (low level echoes maybe due to internal haemorrhage, milk, cellular material, inspissated/concentrated secretions)
• wall thickening, especially if infection present or recent biopsy attempt
• intracystic mass – for example, papilloma
• reduced posterior enhancement, common if small or containing low level echogenic material

Intraductal papillomas
• medium-level soft tissue mass attached to one wall of the duct; may see blood flow to it, may also cause the duct to be dilated, may obstruct and cause distal dilatation.

Fibrosis and epithelial proliferation
• increased echogenicity and often coarseness to the glandular and stromal tissue
• smooth calcifications may be present

Question 19

List the generally accepted risk factors for women developing breast cancer.

Answer 19

• maternal relative with breast cancer (for example, mother, sister, daughter, aunt), especially if young
• increasing age – rare under the age of 30, risk increases steadily with age
• BRCA1 and BRCA2genes. BRCA1 occurs in 1:800 women. BRCA2 is less common, but is associated with early onset breast carcinoma.
• long reproductive cycle – increased risk with early period onset(<15)and/or late menopause(>50)
• obesity, high dietary fat intake in postmenopausal women
• nulliparity, increased risk if never pregnant, slightly less if previously pregnant but no live births
• late age at first pregnancy, that is, first child born to women over 30
• atypical epithelial hyperplasia, due to changes in ductal epithelium
• previous breast cancer
• previous endometrial or ovarian cancer
• previous radiation to the breast
• hormone replacement therapy

Question 20

Discuss the clinical indications of an FNA

Answer 20

Clinical indications:
• tends to be used more as a first choice where the lesion is expected to be cystic or mainly cystic to facilitate aspiration; and
• often performed prior to a core biopsy to obtain a cytological specimen.

Question 21

Discuss the clinical indications of a core biopsy

Answer 21

Clinical indications:
• more commonly used where the lesion is suspected to be malignant or inconclusive; and
• where a previous FNA has been inconclusive.

Question 22

Discuss advantages and disadvantages of a breast FNA

Answer 22

Advantages:
• useful aspiration tool for cystic/mainly cystic lesions;
• relatively quick and easy to perform in trained hands;
• well-tolerated by most patients (often even without the use of local anaesthetic); and
• low chance of bleeding due to fine gauge needle used.
Disadvantages:
• yields only a cytological specimen; and
• sometimes the cellular

Question 23

Discuss advantages and disadvantages of a breast core biopsy

Answer 23

Advantages:
• yields a histological specimen which has the potential to demonstrate the invasiveness of the tumour; and
• usually quite well-tolerated by outpatients with local anaesthetic to the breast.
Disadvantages:
• technically more demanding for the operator and patient;
• more traumatic to the patient;
• greater propensity for the breast to bleed (haematoma development due to larger gauge needle used); and
• chance of tumour seeding along track of needle possible (sometimes disputed).

Question 24

Discuss the various EARLY complications and ultrasound appearances of the breast with implants, including artefacts that aid the diagnosis.

Answer 24

Early complications such as infection or haematoma
These are usually clinically obvious, but ultrasound appearances may show fluid collections of varying echogenicity. Sometimes small anechoic fluid collections may have a simple appearance soon after surgery. The size and position of the collection should be noted. Peri-implant fluid collections may be present for some time with the saline implant.

Question 25

Discuss the various LATE complications and ultrasound appearances of the breast with implants, including artefacts that aid the diagnosis.

Answer 25

2. Late complications
   Deformity due to leakage or rupture:
   This may appear as distortion or lobulation of the prosthesis or as cystic spaces around the implant. Unencapsulated implants may bulge and distort under normal tissue pressures and still not be ruptured. Free silicone may be diffusely extravasated or appear in lumps. Free silicone rupture may give a classical „snow storm‟ appearance – diffuse fine low-level echo shadowing. A ruptured implant will deflate rapidly and may be due to trauma or totally unexpected.

Silicone may extravasate into the surrounding tissue (extracapsular rupture) or be contained within the fibrous capsule formed around the implant (intracapsular rupture). It is very difficult to determine whether it is an encapsulated rupture or merely a bulge in the implant. A sign of an early rupture is the „linguine‟ sign, whereby the recoil of the envelope causes it to contract into the centre of the bag.

Implant rupture may also give the ultrasound appearance of multiple echogenic lines either within or below the anterior surface. Fragmentation of polyurethane bags may also cause long-standing fluid collections, thought to be due to a chronic inflammatory reaction.

Capsular fibrosis:
This is usually more of a clinical diagnosis as the implant capsule becomes firm and hard. On ultrasound, it may appear as bright parallel lines at the surfaces of the prosthesis. The implant may appear distorted.

Echogenic masses:
Calcification and oil cysts may be present. These may appear as echogenic masses of variable hyperechogenicity. Silicone granulomas are a reasonably common appearance, forming at the surface of the silicone bag. They are usually quite palpable and have the ultrasound appearance of an echogenic, well-circumscribed rounded structure close to the edge of the prosthesis. Posterior shadowing will be present. Fragmentation of polyurethane bags may cause debris within fluid collections around the implant.

Contraction:
Due to tissue pressures, undulations and folds may appear within the implant. It may be sometimes difficult to determine if the appearances are of folds or rupture of an implant. Some folds are normal due to tissue moulding.

Question 26

Discuss the various lesion complications and ultrasound appearances of the breast with implants

Answer 26

Breast lesions are still just as likely to appear in the augmented breast. Ultrasound is a useful aid in detecting breast cancer when implants are present as the implant can greatly reduce the quality of the breast imaging in mammography. Studies at present do not show any increased incidence of breast carcinoma when implants are present, but may reduce the ability of early detection via mammography.

Question 27

Discuss the indications for a pleural drainage

Answer 27

• to take a sample of a pleural fluid of unknown origin for diagnosis;
• to remove as much pleural effusion as possible as a therapeutic procedure so that the patient can breathe more easily and comfortably; and
• to sample a pleural, chest wall or mediastinal mass (dependent on easy access under ultrasound control).

Question 28

Discuss the advantages and disadvantages of a pleural drainage

Answer 28

Advantages:
• usually quick to perform;
• real-time visualisation (as opposed to CT);
• optimal plane easily identified;
• can be performed with patients in varying positions (often sitting is easier for the patient with breathing difficulties and gravity helps the fluid to settle in the sampling region);
• portable, therefore can be performed at the patient‟s bedside;
• no use of ionising radiation; and
• usually well-tolerated by the patient.
Disadvantages:
• if the fluid cannot be visualised and a good path for access identified, the procedure should not go ahead (that is, lung lesions can only be sampled if they lie against the chest wall and do not lie under the rib); and
• there is a reasonable chance of pleural being nicked by needle (pneumothorax may be elicited).