Breast Disease

Question 1

What are the differentials for breast pain?

Answer 1

Cyclical & diffuse = often physiological

Non-cyclical & focal = ruptured cysts, injury, inflammation

Presenting complaint in breast cancer

Question 2

What are the differentials for a palpable mass in the breast?

Answer 2

Could be normal nodularity

Hard, craggy, fixed —> worrying sign (cancer)

Invasive carcinoma, fibroadenoma, cysts

note: no woman should be allowed to have a lump in the breast without a firm diagnosis

Question 3

What are the differentials for nipple discharge?

Answer 3

Most concerning if spontaneous & unilateral

Milky = endocrine disorder e.g. pituitary adenoma, OCP

Bloody/serous = benign lesions e.g. papilloma, duct ectasia; occasionally malignant

Question 4

When are women invited for mammographic screening? What are some worrying findings?

Answer 4

Women between 50yrs & 70yrs (extended to 47yrs and 73yrs) invited every 3yrs

Worrying findings = asymmetric densities, parenchymal deformities, calcifications

note: easier to detect lesions in the breasts of older women (more adipose tissue)

Question 5

What is the incidence of breast cancer?

Answer 5

Rare before 25yrs (except for some familial cases)

Incidence rises with age:

• average age at diagnosis = 64yrs
• 77% of cases in women over 50yrs

Most common non-skin malignancy in women (20%)

1/12 women will develop breast cancer at some point

10% of cases are hereditary (3% of overall are BRCA1/2)

Male breast cancers = 1%; increased risk in Klinefelter’s, male to female transsexuals, men treated with oestrogen for breast cancer

Question 6

What are some disorders of breast development?

Answer 6

Polythelia (accessory breast tissue) = excess nipples

Occur along line of milk line remnants (axilla —> breasts —> thorax —-> labia —> inner thighs)

Therefore breast cancer can occur in the axilla/labia

Question 7

What is acute mastitis?

Answer 7

Almost always occurs during lactation, usually Staph. aureus, entering through the nipple cracks & fissures

• erythematous, painful breasts + pyrexia
• may produce abscesses
• antibiotics + express milk

Question 8

What is duct ectasia?

Answer 8

Blockage of lactiferous duct

Usually occurs around menopausal age (50yrs-60yrs)

• may have periareolar mass +/- nipple discharge
• duct dilatation & inflammation
• can mimic carcinoma clinically

Question 9

What is fat necrosis?

Answer 9

Presents as mass, skin changes, or mammographic abnormalities

History of trauma or surgery e.g. seatbelt injury

Can mimic carcinoma clinically & mammographically

Question 10

What is fibrocystic change of the breast?

Answer 10

Commonest breast lesion

May present as a mass or mammographic abnormality

• mass often “disappears” after fine needle aspiration (cyst collapses)
• histology = cyst formation, fibrosis, apocrine metaplasia (pink colour)
• can mimic carcinoma clinically and mammographically

Question 11

What is epithelial hyperplasia of the breast?

Answer 11

Proliferation of epithelial cells which fill and distend ducts and lobules

Slight increase in risk of carcinoma (esp. if atypical)

Incidental finding in biopsy/mammogram

Question 12

What is a papilloma of the breast?

Answer 12

Intraduct lesion consisting of multiple branching fibrovascular cores covered by myoepithelial & epithelial cells

Small duct = multiple & deeper in the breast, slight increased risk of carcinoma, less common than solitary carcinomas

Large duct = lactiferous ducts near nipples

May present with nipple discharge (may be bloody), small palpable mass, or mammographic abnormality

Question 13

What is a fibroadenoma of the breast?

Answer 13

Most common benign tumour of the breast

Can occur at any reproductive age (often “breast mouse”) or mammographic abnormality

• can be multiple & bilateral
• can grow very large and replace most of the breast
• macroscopic = well circumscribed, rubbery, greyish/white
• histology = mixture if stromal & epithelial elements
• localised hyperplasia rather than true neoplasm
• can mimic carcinoma clinically & mammographically

Question 14

What is a phyllodes tumour?

Answer 14

Rare before 40yrs

Presents as rapidly growing masses (months)

More commonly benign; rarely malignant

• can be very large and involve the whole breast
• malignant types behave aggressively, recur locally, & metastasise by blood stream
• need to excise with a wide margin due to risk of recurrence

Histology = nodules of proliferating stroma covered by epithelium (leaf vein appearance)

note: stroma more cellular & atypical than that in adenomas

Question 15

What is gynaecomastia?

Answer 15

Unilateral or bilateral enlargement of the male breast

Caused by relative decrease in androgen effect or increase in oestrogen effect

• puberty & elderly
• can mimic male breast cancer (esp. if unilateral) but has no increased risk of cancer
• occurs in most neonates secondary to circulating maternal & placental oestrogens & progesterone
• transient gynaecomastia occurs in 50% of boys at puberty due to peak in oestrogen production occurring earlier than the testosterone peak

Also occurs in:

• Klinefelter’s syndrome
• cirrhosis of liver (excess of oestrogen)
• gonadotrophin excess (functioning testicular tumour)
• drug-related e.g. spironolactone, alcohol

Question 16

What is the aetiology of breast cancer?

Answer 16

95% are adenocarcinomas

Most common in upper outer quadrant (50%)

Risk factors:

• gender
• uninterrupted menses
• early menarche (

Question 17

What are the genetic mutations associated with breast cancer?

Answer 17

BRCA 1/2 = tumour suppressor genes

• 60%-85% lifetime risk of breast cancer in women
• median age at diagnosis is 20yrs earlier
• prophylactic mastectomies

p53 (Li-Fraumeni syndrome)

Question 18

How can breast cancer be classified?

Answer 18

In situ v.s. invasive

Ductal v.s. lobular

Question 19

Describe in situ breast carcinoma. Give some examples.

Answer 19

Neoplastic population of cells limited to ducts & lobules by basement membrane (does not invade vessels, therefore cannot metastasise) - myoepithelial cells are preserved

Ductal carcinoma in situ (DCIS):

• mammographic calcifications
• can present as mass
• can spread extensively through ducts and lobules
• central (comedo) necrosis with calcification
• non-obligate precursor of invasive carcinoma

Paget’s disease of the breast:

• cells can extend to nipple skin without crossing the basement membrane —> unilateral red and crusting nipple
• any eczematous/inflammatory conditions of the nipple should be biopsied to exclude Paget’s disease

Question 20

Describe invasive carcinoma of the breast. Give some examples.

Answer 20

Invaded beyond basement membrane into stroma, therefore can invade blood vessels and metastasise to lymph nodes and other sites

• usually presents as mass or mammographic abnormality
• by the time cancer is palpable, more than 50% will have axillary lymph node metastases
• peau d’orange = involvement of lymphatic drainage of skin —> blocks drainage —> oedema formation —> hair follicles held in place & rest of breast expands outwards —> resembles orange skin

Invasive ductal carcinoma:

• 70%-80% incidence
• lined by atypical cells when well-differentiated
• lined by sheets of pleiomorphic cells when poorly differentiated
• 10yrs survival = 35%-50%

Invasive lobular carcinoma:

• 5%-15% incidence
• infiltrating cells in single file
• cells lack cohesion (lack of E-cadherin)

Question 21

How does breast cancer tend to metastasise?

Answer 21

Lymphatics —> lymph nodes (usually ipsilateral axilla)

Blood vessels —>

• > bones (most freq.)
• > lungs, liver, brain

Invasive lobular carcinoma can spread to peritoneum, retroperitoneum, leptomeninges, GI tract, ovaries, uterus

note: poorer prognosis with oestrogen receptor negative, HER2 negative carcinomas

Question 22

How is breast cancer diagnosed and treated?

Answer 22

Diagnosis:

• clinical: history & examination
• radiography: mammography + ultrasound
• pathology: fine needle aspiration cytology + core biopsy

Treatment:
LOCAL/REGIONAL =
- breast surgery: mastectomy or breast-conserving (lumpectomy/wide excision) - depends on patient choice, size & site of tumour, size of breast
- axillary surgery (if nodes are involved): sentinel node sampling (reduces risk of post-op morbidity, use dye/radioactivity of the draining lymph nodes) —> axillary dissection —> arm lymphoedema
- post-operative radiotherapy to chest & axilla

SYSTEMIC =

• chemotherapy
• hormonal treatment e.g. tamoxifen (ER positive = 80% of cancers)
• herceptin (monoclonal antibodies against HER2 protein - HER2 positive = 20% of cancers)