III. Inflammatory Conditions
After completing this section you will be able to:
- describe the physiologic hormone-induced changes in the breast, and
- relate the changes to various stages of the female reproductive cycle
- Acute Mastitis and Breast Abscess
This is acute bacterial infection of the breast and may be seen at any age
but typically occurs 2 to 3 weeks at start of lactation. It usually results
from infection via the duct system, which may be blocked by inspissated secretions
resulting in stasis. The most common organism is Staph. aureus. The infection
may progress to abscess formation. A firm, walled-off, non-tender abscess
may be clinically mistaken for breast cancer.
- Fat necrosis
Fat necrosis occurs most frequently in women with pendulous breasts. The
typical presentation is a painless mass located superficially in the breast,
accompanied by retraction or dimpling of the skin due to fibrous scar tissue
extending into the adjacent tissue. They are firm to hard, fixed and irregular
by palpation. A history of trauma may be elicited.
Mammographic examination reveals a spiculated, often poorly defined mass
lesion that may contain punctate or irregular calcifications. The lesion consists
of yellow gray and focally red mass, which may contain foci of cystic degeneration
filled with oily fluid or necrotic fat. Dystrophic calcification is a common
Histologically, there is disruption of adipocytes and hemorrhage. This is
followed by infiltration with histiocytes including multinucleated giant cells,
variable number of lymphocytes and plasma cells, hemosiderin deposition, and
Fat necrosis showing types of inflammatory cells present and fibrosis.
Far necrosis. High power view showing mulinucleate giant cells.
The lesion is completely benign.
Question: What is the clinical importance of fat necrosis?
Mammary Duct Ectasia
Duct ectasia refers to the presence of dilated lactiferous and interlobular
ducts of the breast accompanied by periductal inflammation and fibrosis. The
etiology is not known. The condition is found in the elderly, in whom it occurs
superficially in the lactiferous ducts immediately under the areola. It is
infrequently found in younger women in a peripheral location involving the
intermediate-sized interlobular ducts. This peripheral form may be clinically
difficult to distinguish from cancer.
At surgery, obviously dilated ducts are easily identified. The mass usually
consists of firm breast tissue in which there are prominent ducts containing
pasty, inspissated secretions, which vary in color from white through cream
to brown. Calcification is sometimes seen.
Microscopically, dilated ducts containing eosinophilic, amorphous or granular
acellular debris usually admixed with lipid-laden histiocytes and desquamated
duct epithelial cells are seen. Circumferential inflammatory changes with
chronic inflammatory cells and foam cells are present throughout the thickness
of the duct epithelium and periductal stroma. Rupture of the duct leads to
discharge of contents accompanied by more intense periductal inflammation
with foreign body granulomas. Cholesterol crystals and calcifications may
be found in the intraductal debris. Squamous metaplasia of lactiferous ducts
may be seen in some cases.
The condition is completely benign.
Granulomatous mastitis is a descriptive term, which encompasses many specific
lesions. However, the term has come to be associated with a distinct idiopathic
The age range at diagnosis ranges from 17 to 42 years. Virtually all patients
are parous with mean interval between last pregnancy and disease of 2 years.
Patients present with a distinct firm-hard mass involving any part of the
breast but tends to save the subareolar region. There is no nipple discharge
and bilateral involvement is uncommon.
Microscopically, there is granulomatous inflammatory reaction within and
around lobules comprising epithelioid and Langhans giant cells accompanied
by lymphocytes and plasma cells. In very severe cases, confluent may obscure
the lobulacentric distribution.
Specific conditions such as tuberculosis, fungal infection, sarcoidosis and
granulomatous reaction in carcinoma must be ruled out. Treatment has been
excisional biopsy. Corticosteroids have been effective in resolving the lesions
after specific infectious etiology has been ruled out.
Injection of liquid silicone into breasts for cosmetic augmentation led to
a diffuse foreign body granulomatous reaction throughout the breast. Silicone
is now encased within a synthetic covering and implanted. However silicone
slowly leaks into the surrounding breast tissue leading to the formation of
a fibrous capsule with granulomatous reaction including foreign body giant
Nodularity, skin retraction, hard masses and/or nipple inversion, all of
which may simulate carcinoma, complicate silicone mastitis. Axillary node
enlargement secondary to migration of silicone simulates metastatic carcinoma.
Fine calcifications like those seen in carcinoma may be seen on mammography.
There has been no report of carcinoma following injection of liquid silicone
or leakage from implants.