Gastrointestinal system Part II The oesophagus. A muscular tube Conduction of food and drink...
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Transcript of Gastrointestinal system Part II The oesophagus. A muscular tube Conduction of food and drink...
Gastrointestinal system Part II
The oesophagus
A muscular tube
Conduction of food and drink
Sphincters at top and bottom
Histology
Non-keratinising squamous epithelium
Submucosa Lamina properia Muscularis mucosa Muscular layer Advanticia No mesothelia coverage
Congenital and mechanical disorders (1)
Atresia – often with fistula to trachea Hiatus hernia (presence of stomach in
thoracic cavity) – due to increased intra-abdominal pressure
Sliding hernia>95% Paraesophageal<5%
Hiatal hernia……..
Heart burn&Regurgitation Reflux esophagitis Esophageal ulcer Strangulation
…Mechanical disorders (2)
Achalasia Failure of relaxation of lower
oesophageal sphincter (destruction or degeneration of nerve plexus)
Similar features in Chagas’ disease (South American trypanosomiasis)
Achalasia…..
Apristalsism Lack or decreased LES relaxation Esophageal rest hypertonisity Pre stenotic dilatation&muscle
hypertrophy Dysphagia,regorgitation,aspiration SCC 5% in younger patient
Oesophageal varices
Localised dilatation of lower oesophageal veins
Secondary to portal hypertension (portal vein thrombosis or hepatic cirrhosis)
Haemorrhage can be catastrophic
Mallory weiss syndrome
Longitudinal tearing in GE junction
Hyperemesis Hematemesis Superficial or
deep
Mediastinitis No sequela
Inflammation (oesophagitis)
Acute infective – Herpes virus, Candida. Both seen most commonly in immunosuppressed.
Ingestion of corrosives Chronic reflux through lower
oesophageal sphincter(most common) Uremia,chemotherapy,radiation Sliding hiatal hernia
Herpes oesophagitis
Punched-out ulcers Viral intranuclear inclusions Formation of multinucleated giant cells
(cytopathic effect)
Herpes oesophagitis
Candida oesophagitis
Haemorrhagic mucosa with white plaques
Fungal hyphae and yeast forms on microscopy
Reflux oesophagitis
Common – often without symptoms Mucosa exposed to acid-pepsin and bile Increased cell loss and regenerative activity
Consequences of reflux oesophagitis
Ulceration Stricture Glandular
metaplasia (Barrett’s oesophagus)
Carcinoma
Barrett’s oesophagus
Columnar epithelial cells in lower oesophagus
Variable extent Presence of goblet
cells “intestinal metaplasia” associated with risk of progression to dysplasia/cancer 30-40 X
Oesophageal neoplasms
Benign tumours (rare): squamous papilloma, leiomyoma
Malignant tumours Squamous carcinoma Adenocarcinoma
Presenting symptom - dysphagia
Epidemiology of oesophageal cancer
Squamous carcinoma commonest worldwide 1-2% all cancer death
Adenocarcinoma has very different risk factors and is now the commonest type in Europe/N.America
Scc >90% in other parts In US 50%
Squamous carcinoma
High incidence in Southern Africa (incl. Malawi), China, Iran
Probably diet related (A and B vitamin deficiency, fungal contamination) – tobacco and alcohol also risk factors
Associated with chronic non-specific oesophagitis
Gross morphology
Fungative masses penetrating ulceration Infiltration into the eso.wall
Squamous carcinoma
Often large exophytic occluding tumours
Invasive disease preceded by dysplasia and carcinoma in situ
Adenocarcinoma
Occurs in lower oesophagus
Often associated with Barrett’s oesophagus (progresses through dysplasia to cancer)
Clinical course of oesophageal cancer
Grim! (even with best available resource)
Tumours have commonly spread to regional nodes and/or liver at presentation
No peritoneal lining in mediastinum – local invasion (heart, trachea, aorta) often limits surgery
Any question?