Reproductive - Breast pathology

Question 1

Acute Mastitis

Answer 1

P: Erythematous breast with purulent nipple discharge; absess formation

M: Fissure in nipple from breast feeding -> S. aureus enters

Tx: continued drainage and antibiotics (dicloxacillin)

Question 2

Periductal Mastitis

Answer 2

P: subareolar mass with nipple retraction

M: smokers with low vitamin A -> squamous metaplasia of lactiferous ducts -> duct blockage and inflammation

Question 3

Mammary Duct Ectasia

Answer 3

P: periareolar mass with green-brown nipple discharge (inflammatory debris), multiparous postmenopausal women
Biopsy: Chronic inflammation with plasma cells

M: dilation of subareolar ducts

Question 4

Fat Necrosis

Answer 4

P: Painless mass on exam or abnormal calcification on mammography (saponification)
Biopsy: necrotic fat with associated calcification and giant cells

M: trauma (many not reported) -> necrosis of fat

Question 5

Fibrocystic Disease

Answer 5

P: lumpy breast, usually in upper outer quadrant

M: development of fibrosis and cysts in breast

Benign, but some (ductal hyperplasia, sclerosing adenosis, atypical hyperplasia) are associated with increased risk for invasive carcinoma to both breasts

Question 6

Fibrocystic Changes: Fibrosis

Answer 6

Hyperplasia of breast stroma

No increase risk for invasive carcinoma

Question 7

Fibrocystic Changes: Cystic

Answer 7

Fluid-filled, blue dome. Ductal dilation

No increase risk for invasive carcinoma

Question 8

Fibrocystic Changes: Sclerosing adenosis

Answer 8

Increased acini and intralobular fibrosis; calcifications

2x increased risk for invasive carcinoma to both breasts

Question 9

Fibrocystic Changes: Apocrine metaplasia

Answer 9

Apocrine phenotype changes

No increase risk for invasive carcinoma

Question 10

Fibrocystic Changes: Atypical epithelial hyperplasia

Answer 10

Increased number of epithelial cell layers in terminal duct lobule
5x increased risk for invasive carcinoma to both breasts
In women > 30 years of age

Question 11

Intraductal Papilloma

Answer 11

P: Serous or blood nipple discharge in premenopasual woman

M: papillary growth of luminal and myoepithelial cells into large laciferous ducts. Typically beneath aerola

Slight increased risk for carcinoma with age
Suspect papillary carcinoma (no underlying myoepithelial cells) in post-menopausal women

Question 12

Fibroadenoma

Answer 12

P: well circumscribed, marble-like mass in premenopausal woman
Most common benign neoplasm of the breast

M: tumor of fibrous tissue and glands
Estrogen sensitive - growth and tenderness during pregnancy and menstruation

No increased risk of carcinoma

Question 13

Phyllodes tumor

Answer 13

P: large bulky mass in post-menopausal women (60s)

M: fibroadenoma-like tumor with overgrowth of fibrous component
Biopsy: “Leaf-like” projections

Can be malignant in some cases

Question 14

Breast cancer epidemiology

Answer 14

Most common carcinoma in woman (excludes skin)

2nd most common cause of cancer mortality in women

Question 15

Breast cancer risk factors

Answer 15

Gender
Age (postmenopausal, except hereditary)
Early menarche/late menopause
Obesity
Atypical hyperplasia
First-degree relatives (mother, sister, daughter) with breast cancer

Question 16

Ductal Carcinoma In Situ (DCIS)

Answer 16

P: calcification on mammography; no mass
(other calcifications include sclerosing adenosis and fat necrosis)

M: malignant proliferation of cells in ducts -> fills ductal lumen

No basement membrane penetration

Question 17

Comedocarcinoma

Answer 17

Subtype of DCIS

P: high-grade cells with necrosis and dystrophic calcifications in center of ducts

Question 18

Paget’s diseasse

Answer 18

Subtype of DCIS
P: eczematous patches on nipple; ulceration and erythema

M: DCIS extends up the ducts into skin of nipple
Paget cells: large cells in epidermis with clear halo
(also seen in vulva)

Question 19

Invasive ductal carcinoma

Answer 19

P: physical exam (>2cm) or mammography (>1cm)
firm, fibrous, “rock-hard” mass with sharp margins and small, glandular, duct-like cells. Classic “stellate” morphology.

M: invasive carcinoma that forms duct-like structures; dimpling of skin or retraction of nipple

Worst and most invasive (most - 76% of breast cancers)

4 subtypes: tubular, mucinous, medullary, inflammatory

Question 20

Tubular carcinoma

Answer 20

Subtype of ductal carcinoma
P: premenopausal
M: well-differentiated tubules that lack myoepithelial cells

good prognosis

Question 21

Mucinous carcinoma

Answer 21

Subtype of ductal carcinoma
P: older women (70s)

Abundant extracellular mucin (“tumor cells floating in mucus pool”)

Good prognosis

Question 22

Medullary carcinoma

Answer 22

Subtype of ductal carcinoma
P: BRCA1 carriers, well-circumscribed mass that can mimic fibroadenoma on mammography

M: large, high-grade cells with lymphocytes and plasma cells (fleshy, cellular, lymphocytic infiltrates)

Good prognosis

Question 23

Inflammatory carcinoma

Answer 23

Subtype of ductal carcinoma
P: inflamed, swollen breast; can be mistaken for acute mastitis
Peau d’orange (breast skin resembles orange peel)

M: carcinoma in dermal lymphatics -> block drainage

Poor prognosis (50% at 5 years)

Question 24

Lobar Carcinoma in Situ (LCIS)

Answer 24

P: no mass or calcifications; incidental finding on biopsy

M: malignant proliferation of cells in lobules with no invasion of basement membrane
Lack E-cadherin adhesion protein
Often multifocal and bilateral

Tx: tamoxifen to reduce risk of subsequent carcinoma

Low risk of progression to invasive carcinoma

Question 25

Invasive lobular carcinoma

Answer 25

P: bilateral with multiple lesions in same locations
Single-file pattern cells may exhibit signet-ring morphology (Indian file)

Loss of E-cadherin

Question 26

What is the best prognostic factor for breast cancer staging (TNM)

Answer 26

Metastasis (but many present before)
Spread to axillary lymph nodes most useful (sentinel lymph node biopsy)

Predictive factors for treatment response:
ER, PR, and Her2/neu gene amplication

Triple negative tumors - African American, poor prognosis

Question 27

BRCA1 and BRCA2 mutations

Answer 27

Multiple first-degree relatives with breast cancer, premenopausal tumor, multiple tumors

BRCA 1: breast and ovarian carcinoma
BRCA 2: male breast cancer

Risk remains after bilateral mastectomy (axilla or subcutaneous tissue of chest wall)

Question 28

Male Breast Cancer

Answer 28

P: subareolar mass in older males; nipple discharge (1% of all breast cancers)

M: invasive ductal carcinoma (lobular is rare because male develop few lobules)

Associated with BRCA2 and Kleinfelter syndrome