EXAM #1: PATHOLOGY OF THE BREAST

Question 1

What are the risk factors for malignant breast tumors?

Answer 1

1) Female gender
2) Age i.e. postmenopausal
3) Early menarche/late menarche
4) Obesity
5) Atypical hyperplasia
6) First degree relative with breast cancer

Question 2

In terms of nuclear and extracellular receptors, what kind of breast cancer is more aggressive than the others?

Answer 2

“Triple negative”

• ER
• PR
• HER2

Question 3

What is the single most important prognostic factor associated with breast cancer?

Answer 3

Axillary lymph node involvement

Question 4

What are the two most common invasive breast carcinomas?

Answer 4

1) Ductal (majority)

2) Lobular (minority)

Question 5

What are the least common invasive breast carcinomas?

Answer 5

1) Papillary

2) Inflammatory

Question 6

Breast cancer is most common in which breast, left or right?

Answer 6

Left (upper outer quadrant)

Question 7

If nipple discharge is “bloody” is this likely to be a breast malignancy?

Answer 7

No (this is associated with intraductal papilloma)

Question 8

Peau d’ orange is associated with what type of malignancy?

Answer 8

Inflammatory breast cancer

Question 9

What is the 5-year survival rate of Stage 0 breast cancer?

Answer 9

92%

Question 10

What is the 5-year survival rate of Stage 1 breast cancer?

Answer 10

87%

Question 11

What is the 5-year survival rate of Stage 2 breast cancer?

Answer 11

75%

*Stage 3 and 4 are “bad news”

Question 12

What is DCIS? Is there typically a mass in DCIS?

Answer 12

Ductal Carcinoma in Situ (DCIS)

• Malignant proliferation of cells in the ducts of the TDLU, without invasion of the basement membrane
• Non-palpable in most cases

Question 13

How is DCIS commonly identified?

Answer 13

Early microcalcification on mammography WITHOUT basement membrane penetration

Question 14

What is Comedocarcinoma?

Answer 14

• Subtype of DCIS
• Central DUCTAL CASEOUS NECROSIS surrounded by cancer cells

*Basement membrane is still intact!

Question 15

What is Paget Disease?

Answer 15

Eczematous patches on the nipple resulting from underlying DCIS–DCIS extends up the ducts to involve the skin of the nipple

Question 16

What is a Paget Cell?

Answer 16

Large cells in the epidermis with a clear halo

Question 17

What is the pathognomonic physical exam description of Invasive Ductal Carcinoma?

Answer 17

A mass that is “hard as a rock” with sharp margins

Question 18

What are the microscopic features of Invasive Ductal Carcinoma?

Answer 18

Small duct-like or glandular cells with collagenous stroma i.e. desmoplastic stroma

Question 19

What type of breast cancer is typically bilateral with multiple lesions?

Answer 19

Invasive lobular carcinoma

Question 20

What description is pathognomonic for Invasive Lobular Carcinoma?

Answer 20

“Indian File”

*Cells lack e-cadherin; consequently they don’t stick together and form a single file line

Question 21

How do the cells in Invasive Lobular Carcinoma appear? What do these cells lack?

Answer 21

• Small, uniform, and dyschoesive

- Lack e-cadherin

Question 22

What is unique about medullary carcinoma of the breast?

Answer 22

• Contains large high grade cells growing in sheets with lymphocytic and plasma cell infiltration
• GOOD PROGNOSIS
• Associated with BRCA1

Question 23

Why is Peau d’ orange seen with inflammatory breast cancer?

Answer 23

Carcinoma invades dermal lymphatics, which blocks lymh drainage and leads to the development of the large swollen breast

*Note that this can resemble mastitis, BUT it is NOT responsive to antibiotics

Question 24

In what patient population are fibroadenomas most common?

Answer 24

Women under 35 y/o

Question 25

Is a fibroadenoma a precursor to breast cancer?

Answer 25

No

Question 26

What are the gross features of a fibroadenoma?

Answer 26

Small, mobile, firm mass with sharp edges *Note that it will get worse with higher estrogen (cyclic with menstrual cycle)

Question 27

What is an intraductal papilloma?

Answer 27

- This is a fibrovascular projection into the duct of the TDLU - Contains both epithelial (luminal) cells and myoepithelial cells *Note that this does carry an increased risk of breast cancer

Question 28

What is the hallmark clinical presentation of an intraductal papilloma?

Answer 28

Bloody or serous nipple discharge

Question 29

What is a Phyllodes tumor?

Answer 29

- Fast-growing mass from the periductal STROMA cells - More common in women that are 50-60 y/o i.e. post-menopausal *Note that it MAY become MALIGNANT

Question 30

What are the gross features of a Phyllodes tumor?

Answer 30

- Leaf-like projections | - Large bulky mass with cysts

Question 31

What is proliferative breast disease?

Answer 31

This is the MOST COMMON CAUSE OF BREAST LUMPS in patients 25-menopause i.e. this is fibrocystic change *No increased risk of cancer

Question 32

How does proliferative breast disease present?

Answer 32

- Premenstural breast pain and multiple lesions - Often bilateral - Fluctuation in size of the mass with menstrual cycle and pregnancy

Question 33

What subtypes of proliferative breast disease have an increased risk of malignancy?

Answer 33

1) Sclerosing adenosis 2) Ductal hyperplasia 3) Atypical hyperplasia (if there are atypical cells) *Note that APOCRINE METAPLASIA is NOT associated with an increased risk of breast cancer

Question 34

What is the most common cause of acute mastitis?

Answer 34

S. aureus infiltration during breast feeding leading to bacterial infection/abscess development

Question 35

What antibiotic is used to treat acute mastitis?

Answer 35

Dicloxacillin *Can CONTINUE breast-feeding

Question 36

What causes fat necrosis of breast tissue?

Answer 36

Trauma *Normally results in painless lump that is calcified on mammography