Breast Pathology

Question 1

Ddx of Nipple Retraction:

Answer 1

PERIDUCTAL MASTITIS

BREAST CANCER

Question 2

What is the most common organism responsible for ACUTE MASTITIS?

Answer 2

S. aureus

Question 3

Ddx of MASS in POST-MENOPAUSAL woman:

Answer 3

BREAST CANCER

MAMMARY DUCT ECTASIA

Question 4

Pt is post-menopausal and has a bloody nipple discharge. What is the most likely cause?

Answer 4

PAPILLARY CARCINOMA

Question 5

Pt is pre-menopausal and has bloody nipple discharge. What is the most likely cause?

Answer 5

INTRADUCTAL PAPILLOMA

Question 6

What is the MOST common BENIGN breast neoplasm?

Answer 6

FIBROADENOMA

Question 7

What is the most common tumor seen in PREMENOPAUSAL WOMEN?

Answer 7

FIBROADENOMA

Question 8

Usually, metaplasias are pre-malignant in that it INCREASES the risk of developing future invasive carcinomas. Name 2 instances and 2 exceptions.

Answer 8

2 instances: BARRETTS ESOPHAGUS - nonciliated columnar cell with goblet cell metaplasia increases risk of ADENOCARCINOMA + LUNG squamous metaplasia increases risk of dysplasia + SQUAMOUS CELL CARCINOMA
2 exceptions: BENIGN PROSTATIC HYPERPLASIA + APOCRINE METAPLASIA FIBROCYSTIC CHANGE

Question 9

What are the similarities/differences between FIBROADENOMA and PHYLLODES TUMOR?

Answer 9

SIMILARITY: Both are composed of FIBROUS + GLAND tissue although phyllodes is greater outgrowth of FIBROUS tissue
DIFFERENCES: Phyllodes more prevalent in post-menopausal + can become malignant. Fibro more prevalent in pre-menopausal + BENIGN

Question 10

Is BREAST cancer generally more common in pre-menopausal or post-menopausal women? What is the 1 main exception?

Answer 10

More common in POST-MENOPAUSAL women

Exception = Genetic BREAST CANCER

Question 11

What are 3 causes of GALACTORRHEA?

Answer 11

CAUSE 1: Excess nipple stimulation
CAUSE 2: Hyper-PRL secretion by Pituitary adenoma
CAUSE 3: DA Antagonist Drugs (anti-psychotics)

Question 12

What is the most common cause of PERIDUCTAL MASTITIS? How?

Answer 12

SMOKING - Smokers have VitA deficiency -> Highly specialized epithelium in LACTIFEROUS ducts become squamous metaplasia -> Keratin plugs -> Inflammation behind the blockage

Question 13

What is the most common age population of MAMMARY DUCT ECTASIA (Dilation)?

Answer 13

MULTIPAROUS POST-MENOPAUSAL WOMEN

Question 14

Which breast pathology has BROWN-GREEN PURULENT DISCHARGE?

Answer 14

MAMMARY DUCT ECTASIA

Question 15

Which cells seen in histology are characteristic of MAMMARY DUCT ECTASIA?

Answer 15

PLASMA CELLS (chronic inflammation)

Question 16

What are 2 possible causes of FAT NECROSIS? Which is the more common cause in BREAST FAT NECROSIS?

Answer 16

1. Enzymatic digestion of fat

2. Trauma **- more common cause of breast fat necrosis

Question 17

Ddx of CALCIFICATIONS shown on mammography:

Answer 17

1. Breast carcinoma
2. Sclerosing adenosis
3. Fat necrosis - saponification

Question 18

What is the most common CHNAGE in the PREmenopausal female breast?

Answer 18

FIBROCYSTIC CHANGE

Question 19

Blue-domed cystic appearance + Lumpy breast + fibrosis/cysts/apocrine metaplasia. What am I?

Answer 19

FIBROCYSTIC CHANGE

Question 20

Fibrosis + Cysts + Apocrine metaplasia infers how much increased risk for developing invasive breast carcinoma?

Answer 20

ZERO MINIMAL

Question 21

DUCTAL HYPERPLASIA/ SCLEROSING ADENOSIS infers how much increased risk for developing invasive breast carcinoma?

Answer 21

2X

Question 22

ATYPICAL HYPERPLASIA infers how much increased risk for developing invasive breast carcinoma?

Answer 22

5X

Question 23

What is the most common BENIGN breast neoplasm in PRE-MENOPAUSAL women?

Answer 23

FIROADENOMA

Question 24

What 3 classical features do FIBROADENOMAS have that classify it as a BENIGN tumor?

Answer 24

1. Mobile
2. Well-circumscribed
3. Marble-like mass

Question 25

What age population is PHYLLODES tumor most commonly seen in?

Answer 25

POST-Menopausal

Question 26

What makes PHYLLODES tumor similar to FIBROADENOMA? What makes it different from it?

Answer 26

SIM: Growth of fibrous tissue + glands DIFF: Phyllodes - Overgrowth of particularly the FIBROUS component + Can become malignant, whereas fibroadenoma = ONLY benign

Question 27

What is the most common carcinoma in women by incidence?

Answer 27

BREAST

Question 28

What is the strongest risk factor in developing breast cancer?

Answer 28

1. FEMALE GENDER (99% of breast cancer cases are female) | 2. FAMILY HISTORY

Question 29

What is the most important factor of breast cancer prognosis?

Answer 29

TUMOR SIZE + METASTASIS

Question 30

What is the most UESFUL factor of breast cancer prognosis? How can this be confirmed?

Answer 30

Spread to AXILLARY LYMPH nodes | Confirmed by SENTINEL NODE BIOPSY

Question 31

What are the predictive factors of breast cancer and what response is it associated with?

Answer 31

ER, PR - Response to anti-estrogenic agents (TAMOXIFEN) | Her2/neu gene amplification - Response to anti-Her2/neu mAb (TRASTUZUMAB)

Question 32

What are the 4 subtypes of INVASIVE DUCTAL CARCINOMA?

Answer 32

TUBULAR MUCINOUS MEDULLARY INFLAMMATORY

Question 33

What are 2 histologic features that are characteristic of TUBULAR IDC?

Answer 33

1. Desmoplastic stroma - CT that grows with the tumor to provide structural support 2. Absent myoepithlial cells

Question 34

Which IDC subtype has increased incidence in BRCA1 genetic mutation carriers?

Answer 34

MEDULLARY IDC

Question 35

Which inflammatory cells are evident on biopsy for MEDULLARY CARCINOMA?

Answer 35

Plasma cells + Lymphocytes

Question 36

What should always be considered together on the Ddx of ACUTE MASTITIS?

Answer 36

INFLAMMATORY CARCINOMA

Question 37

What are the 2 diagnostic criteria of INFLAMMATORY CARCINOMA?

Answer 37

CLINICAL PATHOLOGIC ENTITY: CLINICAL - Evidence clinically (erythematous + swollen breast) PATHOLOGIC - Tumor infiltration into dermal lymphatics

Question 38

How does one differentiate between DUCTAL and LOBULAR carcinomas molecularly?

Answer 38

DUCTAL: E-CADHERIN + LOBLUAR: E-CADHERIN -

Question 39

Which breast carcinoma most often pathologically affects BILATERALLY + MULTIFOCALLY?

Answer 39

LOBULAR CARCINOMA IN SITU

Question 40

What makes LCIS different from other breast carcinomas?

Answer 40

Very LOW risk of progression to invasive breast carcinomas Does NOT produce mass/calcifications Considered RISK FACTOR rather than malignant proliferation

Question 41

What is seen on biopsy of LCIS?

Answer 41

Dyscohesive cells - Bec of the lack of E-cadherin

Question 42

What is the Tx of LCIS?

Answer 42

Pharmacologic treatment since it's such low risk of progressing to invasive carcinoma - TAMOXIFEN + close follow up

Question 43

What is the characteristic finding of LCIS biopsy?

Answer 43

SINGLE FILE PATTERN OF GROWTH + NO DUCT FORMATION

Question 44

What are the two single most important gene mutations contributing to HEREDITARY BREAST CANCER?

Answer 44

BRCA1 | BRCA2

Question 45

BRCA1 gene mutations increase the risk of ___

Answer 45

``` BREAST CARCINOMA (specifically MEDULLARY IDC) OVARIAN CARCINOMA ```

Question 46

BRCA2 gene mutations INCREASE the risk of ___

Answer 46

MALE BREAST CARCINOMA

Question 47

What are 2 features that are unique to (or encourage testing of a pt) for HEREDITARY BREAST CANCER

Answer 47

1. Tumor in PRE-MENOPAUSAL woman | 2. MULTIPLE tumors

Question 48

What is seen on biopsy of BREAST FAT NECROSIS

Answer 48

NECROTIC FAT + Associated calcifications + Inflammatory GIANT CELLS