Breast pathology - Non neoplastic lesions

BREAST

LYMPHATIC DRAINAGE AXILLARY (MOSTLY, 85%)) INTERNAL MAMMARY SUPRACLAVICULAR

Histology of the Normal Breast

L O B E

LOBULE

One single ACINUS (alveolus) Epithelial cells MYO-epithelial cells


ACTIVE: about 50-50 Gland/Stroma ratio LACTATING: Mostly Glands (like thyroid!!!), >>>50/50 ATROPHIC: mostly stroma, <<<50/50

Terminal duct

Lobular unit
Terminal Duct Lobular Unit (TDLU)
Cluster of lobules lined by epithelial cells that show brown positivity for estrogen receptor (ER). located in the nucleus.


IIHC with Ab to actin shows the red-brown myoepithelial cell layer around the breast acinus
E
Epithelium
Myoepithelium
The myoepithelial cell layer around the breast acinus

Pregnancy/Lactation

The female breast during pregnancy undergoes hyperplasia & hypertrophy, so that after birth, lactation can occur

Pregnancy/Lactation

Prominent nucleoli
Lactational Change

ATROPHY

Stroma>>>>>glands in atrophy, but lobules and acini are still present architecturally


Triple assessment of breast symptoms. FNAC, fine-needle aspiration cytology; USS, ultrasound scan


Advantages over open biopsy: Fast Cost effective May eliminate an unnecessary procedure Disadvantages: False negatives and false positives

Needle Core Biopsy

Lumpectomy
Mastectomy Modified Radical
Incisional Biopsy

Mammography showing a normal breast (left) and a cancerous breast (right).

Developmental Inflammation: Fibrocystic changes Neoplasm

Accessory nipples.
Supernumerary nipples

ACCESSORY (axillary) BREAST TISSUE

Nipple retraction 1) CONGENITAL 2) ACQUIRED: CARCINOMA 3) ACQUIRED: PIERCING

Macromastia.

Galactocele arises during lactation from cystic dilation of an obstructed duct. May give false suggestion of malignancy


ACUTE, staph most common PERIDUCTAL DUCT-ECTASIA FAT NECROSIS, usually trauma LYMPHOCYTIC, i.e., diabetic GRANULOMATOUS, sarcoid, TB, etc., but mostly idiopathic

ACUTE MASTITIS

ACUTE MASTITIS
Intraductal & periductal inflammatory cells, mostly PMNs.
Cytological smear of nipple exudate in acute mastitis

Mammary duct ectasia, plasma cell mastitis

The inflammation is PERI- ductal rather than INTRA- ductal. A dilated lactiferous ducts, which fill with secretion. ? anaerobic bacterial infection Associated with smoking May mimic ca.

FAT NECROSIS

May mimic a carcinoma


rare, Solitary, subareolar cyst &always dates from lactation. cysts may rupture, inciting an inflammatory reaction, with an indurated focus falsely suggestive of malignancy

GRANULOMATOUS MASTITIS

TB of the breast, is rare, usually associated with active pulmonary TB or TB cervical adenitis

MASS palpable or mammographic NIPPLE DISCHARGE PAIN

Histopathologic findings in a series of women with breast “lumps.”

“FIBROCYSTIC” diseaseNon-proliferative epitheliumProliferative lesions Epithelial - with or without atypia Adenosis - sclerosing adenosis.

They are often multiple, may be bilateral & can mimic malignancy. Dx; FNA &/or US Present suddenly Drainage provides immediate relief.
FIBROCYSTIC DISEASE
Apocrine metaplasia

CYST, GROSS

Fibrocystic changes, microscopic
Minimal or no increased risk of ca: Fibrosis, cystic changes, apocrine metaplasia, mild hyperplasia

Ductal hyperplasia

Normal acinus
Epithelial hyperplasia, can be mild, moderate, or florid judged in part by the number of layers of intraductal epithelium,
Normal Duct

Epithelial hyperplasia, microscopic

Florid ductal epithelial hyperplasia
No cell atypia. Increased risk (1.5 - 2 times) for breast ca
Atypical ductal hyperplasia; Proliferative breast disease with atypia
increased risk (5-fold) for breast ca.
Changes that approach but do not meet diagnostic criteria for CIS

↑ acini/lobule

SCLEROSING ADENOSIS (RADIAL SCAR)
May confused with malignancy
SCLEROSING” ADENOSIS

Atypical hyperplasia with family history or in a premenopausal woman has a risk of invasive carcinoma similar to DCIS
Relative Risk of Invasive Breast Carcinoma

Benign epithelial Benign stromal Premalignant Malignant epithelial (ductal, lobular) (adenocarcinomas) (in-situ, infiltrating) Malignant stromal



Early signs of breast cancer


FIBROADENOMA: 1) Extremely well defined 2) the most common benign tumor of breast. 3) ALWAYS BENIGN 4) CAN FIBROSE OR CALCIFY WITH AGE

Homogeneous lesion with well circumscribed border

Fibroadenoma
Fibroadenomas will “shell out” at surgery

Cleft

Fibroadenoma

Branching compressed ducts

Homogeneous stroma
Fibroadenoma

Intraductal papilloma, Microscopic

May be associated with a serous or bloody nipple discharge