Cytologically Yours: Unknowns: 201401: Case 6

Cytology

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Resident Questions

• Diagnosis?

• Pseudocyst
  • Most common cystic lesion
  • Etiology is diverse (acute pancreatitis, recurrent chronic pancreatitis, trauma, chronic alcohol abuse)
  • Clinically patients present with jaundice, pain, nausea, vomiting, weight loss
  • Pathogenesis
    • leakage of pancreatic enzymes into parenchyma
    • necrosis and chemical peritonitis
    • inflammatory response and pancreatic secretion accumulation occurs and fibrous tissue walls off irritants which causes cyst formation
  • Localized collection of amylase rich pancreatic secretions, necrotic debris and blood
  • Most occur in the tail of the pancreas
  • Usually solitary and unilocular
  • Lack a true epithelial lining

• What are some of the cytologic features that lead you to the diagnosis?

• Variable acute and chronic inflammation
• Histiocytes
• Giant cells
• Necrotic debris
• Granulation tissue may be present
• No epithelium with atypia

• Differential diagnosis?

• Ductal adenocarcinoma with cystic degeneration
  • Atypia in the epithelium
  • Pleomorphic nuclei, cytoplasm variable (vacuolated to dense)
  • Cellular inflammatory background
  • Positive CEA and cytokeratin
• Any neoplasm will have epithelial groups and single cells with atypia
• Big diagnostic problem is the atypia that can be seen in the granulation tissue