4. Breast p143-149 (Implants, Surgery, Post-op)

Question 1

Implants - overview (8)

Answer 1

2 main kinds, silicone and saline.
Saline is less significant if it ruptures, and doesn’t form a capsule so can’t have intracapsular rupture.
Follow up with mammogram and primary care/plastics.
Silicone can have intracapsular and extracapsular rupture.
Can only see extracapsular rupture on mammogram.
Extracapsular creates snowstorm appearance on US. Intracapsular creates a “step ladder” appearance on US and a Linguine sign on MRI.
MRI: Fat Sat T2 to look at implants.

Question 2

Implant rupture types (silicone) (3)

Answer 2

Can have isolated intracapsular.
Cannot have isolated extracapsular (always with intra).
Silicone in lymph node needs MRI to evaluate for intracapsular rupture.

Question 3

Implant location - types (2)

Answer 3

Subglandular (retromammary): implant behind breast tissue, anterior to pectoral muscle.
Subpectoral (retropectoral): Implant between pec major and minor.

Question 4

Silicone implants (3)

Answer 4

Body will form a shell around the implant, allowing intra and extracapsular rupture.
25% will get calcifications around the fibrous capsule.
Implants are NOT a contraindication for core needle biopsy, nor do they increase risk of cancer.

Question 5

Saline implants (6)

Answer 5

Also subglandular or subpectoral types.
Can see through it, differentiating from silicone.
Implant folds and valves can be seen.
If ruptured, saline is absorbed into the body with little clinical significance.
Can be easily burst by biopsy.
Some say physical exam is the best test for saline rupture.

Question 6

Screening mammogram for women with implants (3)

Answer 6

4 views of each breast:
- CC, MLO, Implant displaced CC and Implant displaced MLO
Obviously sensitivity is decreased in women with implants.
Implants are easier to displace if subpectoral.

Question 7

Capsular contracture (4)

Answer 7

Commonest complication of implants, occurs due to contraction of the fibrous capsule.
Causes cosmetic deformity.
Seen more commonly in subglandular silicone implants.
Mammogram: rounding or distortion of the implant

Question 8

Gel bleed (2)

Answer 8

Silicone molecules can pass through semi-permeable implant shell, which is different to rupture.
Silicone in the axillary nodes is seen.

Question 9

Rupture (5)

Answer 9

Top risk factor for rupture is age of implant.
Can occur without trauma. Rupture due to compression mammography is rare.
Saline
- Usually obvious (deflated breast).
- Only of cosmetic significance.
- “wadded up” plastic wrapper on mammogram. No need for US or MRI

Question 10

Silicone rupture (6)

Answer 10

Isolated intracapsular
- Occult on physical exam, mammo and possibly US.
- May see stepladder on US but MRI is more sensitive
Intracapsular with extracapsular rupture
- Obvious on mammogram (dense silicone seen outside the capsule). Normal implant is smooth outlined.
- Silicone outside the implant can go into nodes.
- US: Snow storm” pattern (echogenic with no posterior shadowing). May show lymph node with snowstorm on US.
- MRI: extracapsular silicone is T1 dark, T2 bright.

Question 11

Radial folds (3)

Answer 11

Mimics rupture.
Normal infoldings of the elastomer shell. Usually mimics linguine sign of intracapsular rupture.
Radial folds always connect with the periphery of the implant, rupture folds won’t.

Question 12

Post op breasts (6)

Answer 12

Mammoplasty is done to reduce breast size.
Mastopexy is done to “lift” the breasts, essentially removing skin.
Normal findings post mastopexy
- Swirled appearance affecting inferior breast.
- Fat necrosis/oil cysts
- Isolated islands of breast tissue

Question 13

Keyhole incision (2)

Answer 13

Done for mastopexy and mammoplasty,
Creates swirled appearance in the inferior aspect of MLO

Question 14

Surgical terminology (3)

Answer 14

Lumpectomy - sugical removal of cancer (palpable or not)
Excisional biopsy - Surgical removal of entire lesions
Inclusional biopsy - Surgical biopsy of a portion of the lesion

Question 15

Post biopsy changes (5)

Answer 15

Distortion and scarring are worse within 6-12 months and improve thereafter.
US: Scars should be thin and linear. Focal mass like thickening in a scar is suspicious.
Fat necrosis and benign dystrophic calcifications may evolve over 1-2 years, these are main mimics of recurrence.
Fat necrosis on MR: T1/T2 bright, reduced on fat sat.

Question 16

Risk of recurrence/residual disease - trivia (5)

Answer 16

Local recurrence occurs 6-8% with breast conserving therapy.
Peak time of recurrence is 4 years (most between 1-7).
Without radiation, local recurrence is around 35%.
Early recurrence (<3 years) is usually in the original tumour bed. Later recurrences more likely in a different location.

Question 17

What gets recurrent disease? (6)

Answer 17

Risk of recurrence is highest in premenopausal women (possible underlying genetic issue).
Other risk factors are
- Extensive inarticulate component.
- Tumour with vascular invasion.
- Multicentric tumours
- Positive surgical margins
- Tumour not adequately treated in the first place

Question 18

Residual vs new calcifications (4)

Answer 18

Residual calcifications are not good. Residual calcs near or in the lumpectomy bed correlate with 60% local recurrence rate.
New calcifications:
75% of DCIS will come back as calcifications.
Benign calcifications tend to occur early (2 years) whilst malignant ones occur later (4 years)

Question 19

Sentinel node failure (2)

Answer 19

Sentinel node biopsy is 95% effective, so 5% will have negative sentinel node biopsy with abnormal armpit node.

Question 20

Tissue flap (2)

Answer 20

Cancer will come from residual breast tissue or along the skin scar line.
Screening of the flaps is therefore contraversial, some say not necessary.

Question 21

Specimen radiography (4)

Answer 21

Path reports mentioning “close margins” or “positive margins” mean a very high chance of cancer still in the breast.
Specimen radiographs - look out for 2 things
- is the mass/calcification on the sample
- Is the mass/calcification near the edge of the sample or touching the edge.
Is at the edge, the chance of incomplete excision is around 80% and surgeon needs to be informed.

Question 22

Post radiation changes (5)

Answer 22

Pre-radiation mammogram is important. If you can see residual disease on it, the patient has many more treatment options.
If you discover residual disease after radiation therapy is given, surgery becomes the next option.
Post radiation changes:
Skin thickening and trabecular thickening, normal post radiation, should peak on first post radiotherapy mammogram.
If it gets worse, suggestive of recurrent disease.

Question 23

Breast cancer staging (5)

Answer 23

T1 = <2cm
T2 = 2-5cm
T3 = >5cm
T4 = Any size with invasion (chest wall fixation, skin involvement or inflammatory breast cancer).
Axillary status is most important predictor of overall survival in breast cancer.
Melanoma is most common met to breast

Question 24

Contraindications to breast conservation (5)

Answer 24

Inflammatory cancer
Large cancer size relative to breast
Multicentric (multiple quadrants)
Prior radiation therapy to same breast
Contraindication to radiation therapy (collagen vascular disease)