This document describes non-neoplastic lesions of the breast. It discusses the anatomy of the breast including lobes, lobules, ducts and sinuses. It then covers histology and the three normal phases of the breast. Several non-neoplastic lesions are described including fibrocystic change, inflammation such as mastitis and duct ectasia, and developmental abnormalities. Fibrocystic change is the most common proliferative condition and can cause periodic discomfort through cysts and fibrosis. Inflammatory conditions like mastitis typically present with pain and may lead to abscess.

1. Non-neoplastic lesions
of breast
Dr. Mangala G

3. LYMPHATIC
DRAINAGE
AXILLARY (MOSTLY)
INTERNAL MAMMARY
SUPRACLAVICULAR

4. Anatomy
of Breast
•Lobules
•Acini
•Lactiferous ducts
•Lactiferous sinuses

5. Histology
• Lobe : (10 in whole breast)
• Lobule : (many per lobe)
• Acinus/I, Aka Alveolus/I : (Many Per
Lobule)
• Duct(s) : INTRA- Or INTER- LOB(UL)AR,
leading to the lactiferous ducts in the nipple

6. L
O
B
E

7. LOBULE

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

11. Three Normal Phases
• Active: about 50-50 Gland/Stroma ratio
• Lactating: Mostly Glands (like thyroid!!!),
>>>50/50
• Atrophic: mostly stroma, <<<50/50

13. At birth
• Male and female breasts
• Active secretion (transplacental
passage of maternal hormones)
bilateral breast enlargement
• Colostrum-like secretion ("witch's
milk")
• Recedes several months postpartum

14. Developmental abnormalities
Aplasia and hypoplasia
• Uncommon – associated with
overdevelopment of the contralateral
breast
• Acquired (irradiation – chest wall tumors)
• Unilateral or bilateral amastia (absence of
a nipple, breast ducts, pectoralis major
muscle) – Sex-linked recessive inheritance

15. Ectopic breast:
Supernumerary breast (from ectopic
breast tissue – along the milk lines
(midaxillae – normal breasts – medial
groin and vulva)
• Unilateral axillary breast tissue
Polythelia
• Areola and underlying mammary ducts
Aberrant Breast
•Beyond the usual anatomic extent
(no nipple or areola)

16. Clinical Presentation
 Palpable lump
 Inflammatory mass
 Nipple discharge
 Non-palpable abnormality

17. Inflammation
 Acute MastitisMost clinically important form of mastitis
Breast-feeding  cracks/fissures
in the nipples  bacterial infection
(esp. Staph. aureus)
Usually unilateral—acute inflammation in
the breast can lead to abscess formation
Treatment = surgical drainage (often
under general anesthesia) and antibiotics

18. Recurrent subareolar abscess. When squamous metaplasia extends
deep into a duct, keratin becomes trapped and accumulates. If the
duct ruptures, the ensuing intense inflammatory response to keratin
results in an erythematous painful mass. A fistula tract may burrow
beneath the smooth muscle of the nipple to open at the edge of the
areola.

19.  Mammary Duct Ectasia
 5th and 6th decades
 Affects mainly large ducts
 Periductal chronic inflammation
destruction and dilation of the ducts
with fibrosis
 The underlying cause is unknown

20.  Ma Duct Ectasia Contd…
 Poorly defined periareolar mass; can be
confused clinically/radiologically with
carcinoma
 Can also present as a thick, cheesy
nipple discharge +/- mass
 Periductal fibrosis
  skin retraction

21. INFLAMMATION
 Fat Necrosis
 Uncommon lesion; may be a history
of trauma, prior surgical intervention or
radiation therapy
 Characterized by a central focus of
necrotic fat cells with lipid-laden
macrophages and neutrophils

22. INFLAMMATION
 Chronic inflammation with lymphocytes and
multinucleated giant cells
 Major clinical significance is its possible
confusion with carcinoma (e.g. fibrosis 
clinically palpable mass / Ca2+ seen on
mammography)

23. Fibrocystic Disease/Change
• Most common proliferative condition
of the breast
• Non-neoplastic lesion
• Important because it causes severe
periodic discomfort
• One component –atypical
hyperplasia-high risk for cancer
• Causes palpable lump-mimicking
cancer

24. Fibrosis + Cysts = Fibrocystic Disease

25. Terminology
• Term fibrocystic change is preferred
than fibrocystic disease because some
of the features are similar to
physiological changes
• Terms fibroadenosis & epithelial
hyperplasia – changes in 30-45years
• Cystic hyperplasia –
changes from 40-45 years

26. Aetiopathogenesis
Hormonal imbalances
Excess estrogen
Responsiveness of breast tissue to
hormones(focal)

27. Clinical Features
• Age group-30-55yrs
• Incidence-maximum
just before
menopause,
decreases after
menopause
• C/F vary with age &
underlying
pathology

28. • Gross Morphology:
Younger age –
Diffuse granularity in one /more segments of
breast - nodules upto 5mm
Tender,in premenstrual period
Menopasual age -
Ill defined rubbery mass discrete
swelling indicates cysts,
if fibrosis +, lump is firm

30. Cyst, Gross
Cyst, Microscopic

31. FIBROCYSTIC CHANGE Contd…
• Histology:
–Adenosis
–Sclerosing adenosis
–Epithelial hyperplasia
–Papillomatosis
–Cysts
–Apocrine metaplasia
–Fibrosis

32. Adenosis -
• Increased number of acini/lobules (enlargement
of lobules)
• Structurally normal
• Lobular stroma increased
• Involves mainly epithelium,but myoepithelium
may also be involved
• Correspond to grey-pink nodules on gross and
fine nodules felt clinically

33. Epithelial hyperplasia
• Proliferation of epithelial cells in
interlobular,intralobular ducts and acini ->
solid mass obliterating lumen
Papillomatosis
• Papillae lined by epithelial cells,projecting
into the lumens of dilated ducts/small
cysts.
• Have fibrovascular cores

34. Adenosis ↑ acini/lobule

35. Epithelial
hyperplasia
Sclerosing
Adenosis

36. Fibrocystic Changes- 1.Adenosis.2.Papilloma formation
3.Epithelial hyperplasia.4.Small cysts

37. Sclerosing adenosis
Lobular proliferation
Epithelium involved, myoepithelium
more involved
Increased collagen component in the
tumour - mimic carcinomas clinically
- calcification on mammogram

38. Cysts
Dilatation of acini and terminal ducts
Apocrine metaplasia
Cysts lined by cells resembling
apocrine sweat glands-large columnar
and deeply eosinophilic (pink cell
metaplasia)

39. Fibrosis
Related to hormonal imbalance
changes in the loose connective tissue of
lobules,denser
Atypical hyperplasia
Small ducts,may show abnormalities of
growth, disordered orientation,nuclear
pleomorphism,mitotic figures