1. Volume 136, Issue 1, Pages 56-64 (January 2009)
Squamous Overgrowth Is Not a Safety Concern for Photodynamic Therapy for Barrett's Esophagus With High-Grade Dysplasia 
Mary P. Bronner, Bergein F. Overholt, Shari L. Taylor, Rodger C. Haggitt, Kenneth K. Wang, J. Steven Burdick, Charles J. Lightdale, Michael Kimmey, Hector R. Nava, Michael V. Sivak, Norman Nishioka, Hugh Barr, Marcia I. Canto, Norman Marcon, Marcos Pedrosa, Michael Grace, Michelle Depot 
Gastroenterology 
Volume 136, Issue 1, Pages (January 2009)
DOI: /j.gastro
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2. Figure 1
Squamous overgrowth is shown overlying Barrett's metaplastic glands. A submucosa gland duct is longitudinally sectioned as it extends through the lamina propria of this esophageal forceps biopsy to connect with the surface squamous mucosa. Squamous overgrowth probably develops from the esophageal gland ducts as they extend to the surface.
Gastroenterology  , 56-64DOI: ( /j.gastro )
Copyright © 2009 AGA Institute Terms and Conditions

3. Figure 2
Stratified squamous epithelium completely covers Barrett's neoplastic glands to produce squamous overgrowth. The Barrett's glands exhibit HGD because of the crowded and complex glandular architecture combined with nuclear enlargement, stratification, hyperchromasia, irregular chromatin, and loss of nuclear polarity. This last criterion refers to the loss of a perpendicular orientation to the basal lamina. Despite the fact the squamous mucosa may overgrow HGD or even cancer, the most advanced neoplasia in this study of >38,000 biopsies was never completely buried exclusively beneath squamous mucosa. The most advanced diagnosis was also always present at the surface using 4-quadrant jumbo biopsy sampling protocol every 2 cm throughout the length of the pretreatment Barrett's segment.
Gastroenterology  , 56-64DOI: ( /j.gastro )
Copyright © 2009 AGA Institute Terms and Conditions

4. Figure 3
Time to first squamous overgrowth (S.O.) during biopsy surveillance. PHOPDT, photodynamic therapy with porfimer sodium plus omeprazole; OM, omeprazole.
Gastroenterology  , 56-64DOI: ( /j.gastro )
Copyright © 2009 AGA Institute Terms and Conditions

5. Figure 4
Time to discontinuation from trial of patients with squamous overgrowth (S.O.). PHOPDT, photodynamic therapy with porfimer sodium plus omeprazole; OM, omeprazole.
Gastroenterology  , 56-64DOI: ( /j.gastro )
Copyright © 2009 AGA Institute Terms and Conditions