Inflammations
Breast abscess
- Usually occurs in the lactating breast
- Localised swelling/redness/tenderness
- Pus drained on aspiration
- Antibiotics effective
Fat necrosis
- Often follows trauma
- Localised swelling +/- bruising
- Clinically may mimic cancer
- Resolves spontaneously but slowly
- FNA or core biopsy good for tissue diagnosis
- May be associated with microcalcification - see also benign microcalcification (3)
Chronic fat necrosis with oil cyst formation - left: cystic space formed by necrosis of adipose tissue and lined by foamy macrophages and foreign body giant cells (right).
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Chronic fat necrosis. Low power view on left shows a central stellate scar, a large collection of foreign body giant cells in the upper left
and a collection of free fat droplets in the lower central area. Right hand image shows (A) free fat droplets, (B) a lipoid granuloma and a foreign body giant cell (arrow).
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Chronic fat necrosis - droplets of free fat (left) with foreign body giant cell and foamy macrophage reaction.
Photomicrograph on right shows a central foreign body macrophage with pinkish foamy cytoplasm and an engulfed lipid droplet.
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FNA: Fat necrosis - large numbers of foamy macrophages admixed with lymphocytes and polymorphs,
debris and free fat droplets. Insert shows foreign body giant cell. Main image PAP stained, insert Giemsa.
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Duct ectasia
- May present as a lump or nipple discharge
- Common incidental finding or in duct excisions
- Aetiology unknown
- Inflammatory pattern/process has similarities to fat necrosis
- May be associated with microcalcification - see also benign microcalcification (3)
Duct ectasia, early lesion - accumulation of foamy macrophages beneath luminal duct epithelium.
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Series of images from cases of duct ectasia. The earliest lesions are characterised by the accumulation of foamy macrophages between the basement membrane and the epithelium and also within duct lumens.
Later lesions show periductal chronic inflammation whilst the most advanced lesions show marked periductal scarring. Superimposed (dystrophic) calcification may be seen.
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The following set of photographs show an unusual granulomatous variant of duct ectasia
with numerous foreign body giant cells (presumably reacting to lipid) within duct lumina
with periductal granulomatous inflammation and stromal chronic inflammation and fibrosis.
Unusual granulomatous variant of duct ectasia
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Granulomatous Lobular Mastopathy
The following images illustrate the pathology of this uncommon inflammatory condition of unknown aetiology. Its importance
relates to the problem that it can be mistaken clinically for carcinoma because it can present as a palpable irregular hard mass
and its partial obliteration of lobular units could lead to the mistaken inpression of an infiltrative process
histologically. The similarities histologically between this condition, granulomatous duct ectasia and mastitis obliterans suggest to me that these conditions are related.
Granulomatous Lobular Mastopathy
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See also Image of the month 2010/6 Granulomatous lobular mastopathy
Mammary Duct Fistula
- Presents as peri-areolar discharge in premenopausal women
- Chronic condition and difficult to treat
- Maybe bilateral
- Invariably occurs in smokers
- Aetiology unknown
The images below are from an excised fistula track. The condition may
require a number of operations. The track is characteristically lined by keratinising
squamous epithelium and granulation tissue with chronic inflammation of surrounding tissues.
Mammary duct fistula
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Radiation injury
- Often seen following conservation surgery for breast cancer
- May occur at any time after about 6 months following treatment
- Commonly presents as breast thickeneing
- Less commonly as a lump
- Changes include:
- Hyalinisation of collagen and necrosis
- Vascular changes
- Characteristic radiation fibroblasts - see images below
Diabetic Mastopathy
Amyloidosis
- Very uncommon in the breast
- May be identified incidentally in a patient with systemic amyloidosis
- May very rarely present as a mass lesion - amyloid tumour
Amyloid tumour of the breast - this was clinically and radiologically suspicious
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