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WEBS, RINGS, AND STENOSISEsophageal mucosal webs are uncommon ledgelike protrusions of the mucosa into the esophageal lumen. These are semicircumferential, eccentric, and most common in the upper esophagus. Well-developed webs rarely protrude more than 5 mm into the lumen, with a thickness of 2 to 4 mm. The webs consist of squamous mucosa and a vascularized submucosal core. Webs can be congenital in origin, or they may arise in association with long-standing reflux esophagitis, chronic graft-versus-host disease (GVHD), or blistering skin diseases. When an upper esophageal web is accompanied by an iron-deficiency anemia, glossitis, and cheilosis, the condition is referred to as the Paterson-Brown-Kelly or Plummer-Vinson syndrome, with an attendant risk for postcricoid esophageal carcinoma. Esophageal rings are concentric plates of tissue protruding into the lumen of the distal esophagus. One occurring above the squamocolumnar junction of the esophagus and stomach is referred to as an A ring. One located at the squamocolumnar Figure 17-1Esophageal atresia and tracheoesophageal fistula. A, Blind upper and lower esophageal segments. B, Fistula between blind upper segment and trachea. C, Blind upper segment, fistula between blind lower segment and trachea. D, Blind upper segment only. E, Fistula between patent esophagus and trachea. Type C is the most common variety. (Adapted from Morson BC, and Dawson IMP, eds., Gastrointestinal Pathology. Oxford, Blackwell Scientific Publications, 1972, p. 8.) Figure 17-2Major conditions associated with esophageal motor dysfunction. Figure 17-3Esophageal laceration (Mallory-Weiss tears). Gross view demonstrating longitudinal lacerations extending from esophageal mucosa into stomach mucosa (arrow). (Courtesy of Dr. Richard Harruff, King County Medical Examiner's Office, Seattle, WA.) Figure 17-4Esophageal varices. A, A view of the everted esophagus and gastroesophageal junction, showing dilated submucosal veins (varices). The blue-colored varices have collapsed in this postmortem specimen. B, Low-power cross-section of a dilated submucosal varix that has ruptured through the mucosa. A small amount of thrombus is present within the point of rupture. C, Hepatic venogram after injection of dye into portal veins (PV) to show a large tortuous gastroesophageal varix (arrow) extending superiorly from the patent main portal vein. (C, courtesy of Dr. Emily Sedgwick, Brigham and Women's Hospital, Boston, MA.) Figure 17-5Reflux esophagitis. Low-power view of the superficial portion of the mucosa. Numerous eosinophils within the squamous epithelium, elongation of the lamina propria papillae, and basal zone hyperplasia are present. Figure 17-6Barrett esophagus. A, B, Gross view of distal esophagus (top) and proximal stomach (bottom), showing A, the normal gastroesophageal junction (arrow) and B, the granular zone of Barrett esophagus (arrow). C, Endoscopic view of Barrett esophagus showing red velvety gastrointestinal mucosa extending from the gastroesophageal orifice. Note the paler squamous esophageal mucosa. Figure 17-7Barrett esophagus. Microscopic view showing squamous mucosa and intestinal-type columnar epithelial cells (goblet cells) in a glandular mucosa. TABLE 17-1-- Factors Associated with the Development of Squamous Cell Carcinoma of the Esophagus Dietary Deficiency of vitamins (A, C, riboflavin, thiamine, pyridoxine) Deficiency of trace elements (zinc, molybdenum) Fungal contamination of foodstuffs High content of nitrites/nitrosamines Betel chewing Lifestyle Burning-hot beverages or food Alcohol consumption Tobacco use Urban environment Date: 2016-04-22; view: 1464
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