This document discusses the anatomy and development of the breast as well as several benign breast diseases. It begins by describing the development of the breast from early gestation through puberty and adulthood. It then discusses the arterial, venous, and lymphatic supply of the breast. The majority of the document lists and describes various benign breast diseases including inflammatory conditions like duct ectasia and fat necrosis. Proliferative and non-proliferative fibrocyctic changes are also discussed along with specific conditions like sclerosing adenosis, radial scar, apocrine metaplasia, ductal papilloma, and diabetic mastopathy. Additional benign breast tumors mentioned include fibroadenoma, phyllodes tumor, hamart

1. Mays Yousuf Ismail© BenignBreastdiseases Al-Qudsuniversity;Palestine
 Breast is a modified sweat gland. It's development starts at gestational week 6.
 Pubertymarksthe beginningof the glandularmaturation,butfull breast differentiation
occurs only in pregnancy and lactation.
 At birth: 10-12 primitive ducts are around the nipple
 Pre-puberty: Each duct branches and canalizes
 Pubertytoadult:more branching,canalization,anddifferentationof terminal ductunit.
 Terminal ductunitmaturation:alveolarbuds formation thatfinallydifferntiate to acini.
 Each 11 acini collect around a terminal duct to make Lob 1.
 Lob 1: pre-puberty
 Lob 2: puberty
 Lob 3: pregnancy and lactation.
 Arterial supply:
1. Internal thoracic artery: anterior perforating arteries
2. Axillary artery: lateral thoracic and thoracoacromial arteries.
3. Intercostal arteries.
4. The venous supply corresponds to the arteries.
5. The intercostal veins: mets to the brain through comunication via space baston.
 Lymphatics:
1. Level 1: lateral and lower:anteriorandposteriorandlateral to the pectoralisminor
2. Level 2: behind: central
3. Level 3: medial and above: apical "halsted"
Lymphatics cross the diaphragm but not the midline, in contrast to the veins.
 Benigndiseases of the breast: occur in the 2nd
decade, and peak in the 4th
-5th
decades.
 Inflammatory
Duct ectasia:
Subareolar non-cyclical pain with bilateral multiple nipple discharge.
Nipple retraction/subareolar mass/Hx of abscess or fistula/eczema.
Tx: total duct excision.
Fat necrosis:
May follow any inflammatory/proliferative/traumatic breast disease.
 Fibrocystic disease: found in almost every woman. (90% of women).
All types carry a variable risk of cancer. Hormonal

2.  Divided into:
1. Proliferative with atypia:atypical ductal and lobular hyperplsia
2. Proliferative withoutatypia:radial/sclerosng/papiloma/ducthyperplsia
3. Nonproliferative:cyst/apocrine metaplasia/fibroadenoma/calcification
/mild ductal hyperplasias
Sclerosing adenosis:
Beningn disease of the perimenopausal women. Ductal proliferation with stromal
fibrosis. It has multiple calcified microcysts. It's totally benign.
Radial scar:
Central sclerosiscircledbyapocrine metaplasiaandpapillomasatthe terminal ducts
Apocrine metaplasia:
Columnar cells with eosinophilic cytoplasm and granules resemble sweat glands.
Ductal papilloma and papillomatosis:
Minimum of 5 intraductal hyperplasia. Benign mostly.
Diabetic mastopathy:
Lymphocytic infiltration in DMtype 1. Painless immobile mass. Do US then biopsy.
PASH:
Benign stromal proliferation in pre (post) menopausal women on HRT.
 Fibroadenoma:
1. An abberation of normal development occurs in women 20-30s.
2. No riskof cancer unlesscomplex (cystic/calcifications/papilloma…) <0.3%
3. Enlarge in pregnancy; hormonal
4. No cancer risk
5. Regress alone in 7 years.
6. Usually patient < 30 years
 Phyllodes tumor: cystosarcoma
1. Unilateral single mass mainly ROQ increases in size.
2. Cancer potential.
3. Removal with safety margin 2-5 cm is enough.
4. Usually patient > 30 years
5. Don't look for LNs. First mets to the lung.
 Another name for hamartoma is adenolipoma.
 Nipple adenoma: nipple mass in pregnant or lactating women. Might erode and
bleed. Simple excision.