Inflammatory Disorders of the Breast

Question 1

What causes inflammatory disorders of the breast?

Answer 1

• Infections
• Autoimmune disease
• Foreign body-type reactions to extravasated keratin or secretions

Question 2

How can inflammatory breast cancer mimic inflammation?

Answer 2

• Obstructing dermal vasculature with tumor emboli

- Should always be considered in a women with an erythematous swollen breast

Question 3

What are some inflammatory disorders of the breast?

Answer 3

• Acute mastitis
• Squamous metaplasia of lactiferous ducts
• Duct ectasia
• Fat necrosis
• Lymphocytic mastopathy
• Granulomatous mastitis

Question 4

What can all inflammatory disorders of the breast be confused with?

Answer 4

• Cancer

Question 5

How do you tell inflammatory disorders apart from cancer?

Answer 5

• Look into the clinical setting, associations, biopsy findings, and treatment

Question 6

When does acute bacterial mastitis typically occur?

Answer 6

• During the first month of breastfeeding

Question 7

What causes acute bacterial mastitis?

Answer 7

• Local infection when the breast is most vulnerable due to cracks and fissures in the nipples
• Staphylococci infection often leads to single or multiple abscesses, whereas streptococci cause spreading infection in the form of cellulitis

Question 8

What is squamous metaplasia of lactiferous ducts (SMOLD) also known as?

Answer 8

• Recurrent subareolar abscess
• Periductal mastitis
• Zuska disease

Question 9

What does SMOLD present with?

Answer 9

• Painful, erythematous subareolar mass that mimics a bacterial abscess
• A fistula tract often develops under the smooth muscle of the nipple and opens onto the skin at the edge of the areola (esp. in recurrent cases)
• In many women, nipple inverts due to traction produced by inflammation and scarring

Question 10

What is a common association with SMOLD?

Answer 10

• 90% of women affected are smokers
• Also suggested that a relative deficiency of vitamin A associated with smoking or toxic substances in tobacco smoke alters the differentiation of the ductal epithelium

Question 11

What is the key feature of SMOLD?

Answer 11

• Keratinizing squamous metaplasia, which extends into the nipple duct well past the usual point of transition from squamous to glandular epithelium

Question 12

What happens as the keratin sheds from the cells in SMOLD?

Answer 12

• Keratin cells are trapped and plug the ductal system causing dilation and eventually rupture of the duct
• This causes an intense chronic granulomatous inflammatory response to develop once keratin spills into the surrounding periductal tissue
• With recurrences, a secondary anaerobic bacterial infection may supervene and cause acute inflammation/abscess

Question 13

How does duct ectasia present?

Answer 13

• Palpable periareolar mass that is often associated with thick, white nipple secretion and occasionally with skin retraction

Question 14

When does duct ectasia present?

Answer 14

• Fifth or sixth decade in usually multiparous women

Question 15

How is duct ectasia diagnosed?

Answer 15

• Due to difficulties in distinguishing it on clinical and radiologic grounds from invasive carcinoma, a radiopaque material is injected into the nipple to view the ductal structure

Question 16

What are the ectatic dilated ducts filled with?

Answer 16

• Inspissated secretions and numerous lipid-laden macrophages

Question 17

What happens in duct ectasia when the duct ruptures?

Answer 17

• A marked periductal and interstitial chronic inflammatory reaction ensues, consisting of lymphocytes, macrophages, and variable number of plasma cells

Question 18

What does subsequent fibrosis cause in duct ectasia?

Answer 18

• An irregular mass with skin and nipple retraction

Question 19

How does fat necrosis present?

Answer 19

• Commonly seen in the setting of trauma or surgery

- Painless, palpable mass, skin thickening or retraction, or mammographic densities or calcifications

Question 20

What kind of necrosis is seen in fat necrosis?

Answer 20

• Liquifactive

Question 21

What is lymphocytic mastopathy also known as?

Answer 21

• Sclerosing lymphocytic lobulitis

Question 22

How does lymphocytic mastopathy present?

Answer 22

• Uncommon fibroinflammatory lesion that courses with the presence of benign breast nodules, and may clinically and radiologically mimic a carcinoma
• May appear as a single or multiple, uni or bilateral, synchronous or asynchronous, ill-defined, hardened mass

Question 23

Who is most likely to have lymphocytic mastopathy?

Answer 23

• Women with T1DM (insulin dependent)
• Autoimmune thyroid disease
• Hypothesized to have an autoimmune basis

Question 24

What are the masses in lymphocytic mastopathy associated with?

Answer 24

• Areas of densely collagenized stroma, a feature that may make it difficult to obtain lesional tissue by needle biopsy

Question 25

What is the cause of granulomatous inflammation of the breast?

Answer 25

• Could be a manifestation of systemic granulomatous diseases or of inflammatory or infection disorders (sarcoidosis, TB)

Question 26

Who is affected with granulomatous inflammation?

Answer 26

• ONly in parous women

Question 27

What are the granulomas associated with in granulomatous inflammation?

Answer 27

• Lobules and may contain lipid vacuoles surrounded by neurtophils

Question 28

What is the histologic pattern of granulomatous inflammation also seen in?

Answer 28

• Cystic neutrophilic granulomatous mastitis (caused by lipophilic Corynebacterium)

Question 29

Who is most likely to have a localized infection due to either myobacteria or fungi?

Answer 29

• Immunocompromised patients

- Individuals that have foreign objects like a nipple piercing or breast prostheses