• bacterial
• mumps
• Sjogren's syndrome

• acute/chronic inflammation of parotid
• characterized by swelling and tenderness of gland early-on
• followed in many cases by xerostomia (lack of saliva and dry mouth) as function of the gland is diminshed

• most often related to decrease in salivary flow during times of significant debilitation/obstruction of the duct by a stone/stricture
• leads to migration of oral flora (ex: S. aureus) into the gland

• acute ssRNA virus infection
• microscopic morphology
  • necrosis of glandular tissue
  • inflitration of organ with lymphocyts and macrophages

• characterized by chronic inflammation of salivary tissue and lacrimal glands as prominent targert organs
• gross appearance
  • causes xerostomia and keratoconjunctivitis sicca (dry eyes)
  • cause variable involvement of other tissue sites
• gross/microscopic pathology 
  • chronic lack of saliva results in atrophy, inflammation, and fissuring of oral mucosa

• destruction of acini and ducts
• dense lymphocytic infiltrate (mostly T cells)
• stroma preserved
• occasional islands of hyperplastic myoepithelial cells

• pleomorphic adenoma (mixed tumor)
• mucoepidermoid carcinoma

• epidemiology
  • most common salivary tumor (benign)
  • middle aged females
• clinical significance
  • benign tumor
  • prone to occur in parotid, growing as slowly enlarging, painless, mass
  • surround/compress such local structures as the facial N.

• mixture of epithelial cells that are ductal or myoepithelial cells
  • forms ductules or nests/cords of cells, respectfully
• surrounding myxoid-mucoid stroma
• has fibrous capsule
  • may have extension that will regrow if left behind at surgery (NOT recurrence or metastasis)

• epidemiology
  • most common malignant tumor of salivary tissue
  • predominantly in parotid
  • no gender or age predominance
• prognosis
  • well differentiated tumors have good prognosis (grow in expansile manner at primary site)
  • poorly differentiated tumors can metastasize and have a poor prognosis

• well differentiated
  • duct like and cystic spaces lined by squamous and mucus secreting cells
• poor differntiated
  • fewer mucus secreting cells
  • looks more like squamous carcinoma

• common epithelial cell layer and lamina propria (non epithelial CT of mucosal layer) bordered circumferentially by muscularis mucosa (longitudinally oriented smooth muscle layer)
• lamina propria contains vessels and specialized or mucus producing glands
• submucosal layer contains vessels and lymphatcs, nerves, Meisner's complex, submucosal glands
• submucosa bordered by muscularis propria
  • inner (circular), outer (longitudinal) smooth muscle layers
  • in between layers in Auerbach's plexus
• serosal layer (poorly developed in esophagus)

• upper 1/3: skeletal muscle (decreases in amount as you go down esophagus)
• lower 2/3: smooth muscle
• mucosa changes abruptly at GE junction with transition to gastric mucosa
• mucosal epithelium composition
  • nonkeratinized squamous epithelial cells
    • function- provides a relatively resistant lining against the abrasion of undigested food

• UES (cricopharyngeal zone) at upper end to protect against reflux of contents into lung and to minimize entry of air during swallowing
• LES (gastroesophageal junction) to protect against the reflux of acid from stomach

• dysphagia (due to poor motility or obstruction)
• odynophagia (pain on swallowing)
  • especially with associated inflammation
• hematemesis (when injury/ulceration erodes into submucosal vessels)
  • massive hemorrhage can result in submucosal veins are dilated by portal pressure (varices)

• primary
  • idiopathic
  • epidemiology- young adults
  • associated with increase risk of carcinoma
• secondary
  • associated with infections
    • Chagas disease
    • neuromuscular diseases (polio, DM)

• associated with:
  • progressive dysphagia
  • probably nocturnal regurgitation with possible aspiration
• cause of poor or absent peristalsis and dilation of esophagus
  • increase tone of LES
  • failure to relax LES with normal swallowing
• histopathology
  • decrease/loss of ganglion cells in myenteric plexus
  • hypertrophic muscle and/or thinning of dilated muscle and esophageal wall above

• associated with dysphagia and regurgitation
• types
  • pulsion/Zenker's diverticulum
  • traction diverticulum

• location- proximal
• associated with weakening of pharyngeal constrictor muscles
• may be true (involve full wall thickness) or false (no muscle) diverticulum

• location- usually mid-lower esophagus
• usually consist of entire wall thickness
• occurs in association with fibrous adhesions

• most are silent
• symptoms appear with complications like GERD and esophagitis, resulting in heart burn
• protrusions of cardia above diaphragmatic hiatus cause two types of hernia:
  • sliding- symmetrical extrusion of cardia through diaphragmatic crura which can shift position above and below diaphragm
  • fixed- separate protrusion of stomach that doubles back against esophagus and become trapped against diaphragm

• definition- dilated portosystemic veins mainly within submucosa
• cause- portal HTN
• associated with:
  • hematemesis
  • melena
• clinically silent, except for when there are complications of hemorrhage

• definition- hematemesis related to a longitudinal linear laceration at the gastroesophageal junction
• may remain superficial or penentrate through wall, resulting in vomitting (against closed LES)

• Plummer-Vinson syndrome/web (upper esophagus)
• Schatzki's ring (lower esophagus)
• histological appearance
  • folds of mucosa with a vascularized fibrous core

• esophageal web associated with:
  • increased risk for squamous cardcinoma
  • severe iron deficiency anemia
  • dysphagia

• definition- acute (eosinophils, neutrophils), and chronic (lymphocytes) inflammation of mucosa and possibly submucosa (with possible associated ulceration)
• chronic histopathology: mucosa can react with:
  • elongation of papillae
  • increase in small vessels
  • hypertrophy of basal cells
  • thickening of epithelial cell layer
  • metaplasia

• predisposing factors
  • increased abdominal pressure (pregnancy, obesity)
  • decrease LES tone (hiatal hernia, smoking, alcohol)
• histopathology- metaplasia (chronic exposure to gastric contents)

• histopathology
  • columnar cell interstitial metaplasia of epithelium which includes intestinal epithelial cells full of acid-mucin
• assopciated with inrease risk of develpoing dysplasia that progressing to esophageal adenocarcinoma

associated with immunosuppression

• CMV- endothelial cells are predominant target showing intranuclear inclusings
• HSV- epithelial cells are predominant target showin giant cells and vacuolar nuclei

associated with immunosuppression

• Candida albicans
  • epithelium is most common target
  • ulceration can occur

• esophageal squamous cell carcinoma
• esophageal adenocarcinoma

• epidemiology
  • predominately males
  • blacks
  • most common type world wide
• risk factors
  • alcohol
  • smoking
• pathology
  • location- most in mid esophagus
  • arises from sites in squamous epithelium

• epidemiology
  • no gender predominance
  • predominantly white
• risk factors
  • GERD
  • Barrett's esophagus
• histopathology
  • location- lower esophagus
  • tumor cells may occur in morphological pattern consistent with intestinal glands or as diffusely infiltrative mucin-positive cells