Ductal carcinoma in situ (DCIS)

Question 1

Properties

• Basement membrane
• Disruption of lobules
• Papillary, cribriform patterns
• Necrosis and secretory activities
• Types
• Involvement of nipple skin
• Bilaterality
• Hormonal status

Answer 1

• Basement membrane
  
  • Intact
• Disruption of lobules
  
  • Yes
• Papillary, cribriform patterns
  
  • Yes
• Necrosis and secretory activities
  
  • Yes, thus positive calcifications
• Types
  
  • Solid, cribriform, non-comedo, comedo
• Involvement of nipple skin
  
  • Yes, Paget disease of nipple
• Bilaterality
  
  • 10 to 20%
• Hormonal status
  
  • Variable

Memory aid:

• Intact BM because this is not inasive
• It may seem counterintuitive but _D_CIS disupts lobules, _L_CIS does not
• Cribriform – duck (in ADH)
• The Duck is Pa_nget and calcified

Question 2

Is this a risk factor or a precursor to invasive breast cancer?

Answer 2

True anatomic precursor

Question 3

Paget disease of the nipple occurs ____ (rarely/commonly)

Answer 3

Rarely (1% to 4% of cases)

Question 4

PE finding in Paget disease and its mechanism

Answer 4

Erythematous eruption with a scaly crust

Malignant cells extend from ductal DCIS into nipple skin without crossing the basement membrane

↓

Cells disrupt the epithelial barrier and allow extracellular fluid to seep out

↓

Creation of an erythematous eruption with a scaly crust

Question 5

Paget disease underlying cause

• With palpable mass
• Without palpable mass

Answer 5

• With palpable mass
  
  • Most have invasive carcinoma
• Without palpable mass
  
  • Underlying DCIS
• Summary:*
• It is usually associated with the two

Question 6

Pathognomonic histologic finding in Paget disease

Answer 6

Large, pale, vacuolated cells in the rete pegs of epithelium

Question 7

Comedocarcinoma vs noncomedo DCIS histologic finding

Answer 7

• Comedocarcinoma
  
  • Ducts and lobules dilated by sheets of high-grade pleomorphic cells with zones of central necrosis
• Noncomedo DCIS
  
  • Monomorphic population of cells of varying nuclear grades; patterns include cribriform, solid, papillary, and micropapillary

Question 8

Microinvasion is defined by stromal invasion less than ____

Answer 8

0.1 cm

Question 9

Paget disease must be differentiated from what disease? How?

Answer 9

• Melanoma
  
  • Paget disease – ⊕ CEA
  • Melanoma – ⊕ S-100