 Risk factors: hiatal hernia, duodenogastric  reflux,delayed acid clearance time, ↓LESp  Adult disorder → 376 per  Irreversible condition  M/F = 2/1

 Specialized columnar epithelium with goblet cells (positive for Alcian blue in pH:2.5)  Absence of goblet cells is insufficient to make a definitive diagnosis  “Barrett cytokeratin 7/20 pattern”

 Negative for dysplasia  Indefinite for dysplasia  Low grade dysplasia  High grade dysplasia

 Surface maturation (low power)  Architecture (low power)  Cytologic features  Inflammation and erosions/ulcers

 Surface epithelium more mature than underlying glands  Normal architecture  Nuclear stratification - ↑N/C, small nucleoli, mitoses are normal in Deeper glands  Nuclear polarity and, smooth outlines are preserved in Deep and superficial

 Nuclear membrane irregularity, hyperchromasia in Deep,  with normal maturation to surface  Active PMN infiltration  No polarity disturbance  No architectural abnormality

 Extension of cytological abnormalities to surface (at least focally)  No maturation to surface  Abundant inflammation, prominent nucleoli, abnormal architectures and loss of polarity are not LGD features.

 Prominent cytologic abnormalities  Markedly distorted glands  Little intervening lamina propria

 DNA content (flowcytometry)  P53 → progression