Upper Gi pathology Flashcards
Where is the most common spread of head and neck cancers?
Lymph nodes in the neck, usually on the same side
What is a classical presentation of mouth cancer?
An ulcer which persists without a definite, identifiable cause (should heal within 2-3 weeks)
What are the main risk factors of oral cancer?
- Smoking
- Alcohol
- HPV can be a factor in some cases (mainly tonsil, oropharynx)
What are the histological layers of the oesophagus?
- Mucosa
- Muscularis mucosae
- Submucosa
- Muscularis propria
- Adventitia
What is the mucosa in the oesophagus lined by?
Non-keratinising stratified squamous epithelium
What is the pathogenesis of reflux oesophagitis?
- Acid, bile and digestive enzymes injure the squamous epithelium lining of the oesophagus
- Increased numbers of inflammatory cells and basal hyperplasia
- Reflux of gastroduodenal secretions
Name a fungal infection of the oesophagus
Candida albicans
What infection of the oesophagus can occur in immunocompromised patients?
Herpes simplex virus
What conditions result in inflammation of the oesophagus?
- Peptic oesophagitis/GERD: reflux of acid/bile
- Caustics: NaOH, caustic soda
- Pills: iron, bisphosphonates, tetracyclines
What is the appearance of candida oesophagitis?
White spots
What confirms a candida albicans infection of the oesophagus?
- PAS stain
* Spores and hyphae seen
What are the symptoms of eosinophilic oesophagitis?
Dysphagia/food sticking
What is eosinophilic oesophagitis?
Eosinophils infiltrate the epithelium, it has an allergic aetiology
What is eosinophilic oesophagitis responsive to?
Steroids (fluticasone)
What is the endoscopic appearance of eosinophilic oesophagitis?
Ring like trachealization
What is the histological appearance of eosinophilic oesophagitis?
Large numbers of brightly staining eosinophils infiltrating the oesophageal squamous epithelium
Name two oesophageal cancers
- Squamous carcinoma
* Adenocarcinoma
What is squamous carcinoma of the oesophagus associated with?
Smoking and drinking
What is adenocarcinoma of the oesophagus associated with?
GERD (gastro-oesophageal reflux) and obesity
What is Barrett’s oesophagus?
- Metaplastic response to mucosal injury
- Squamous cells become glandular (usually intestinal with goblet cells)
- Associated with benign strictures but also with adenocarcinoma
Describe the risk of progression to cancer of Barrett’s oesophagus
- If no dysplasia or aneuploidy the risk is low
* Definite low or high grade dysplasia have a higher risk but the progression to cancer is still low
What is the Seattle biopsy protocol?
- Four biopsies every 2cm every 2 years
* Checking for progression to cancer in patients with Barretts oesophagus
Describe the spectrum of dysplasia
- Inflammation, reactive changes
- Indefinite for dysplasia - when you cannot be certain
- Mild, moderate (low grade) dysplasia
- Severe (high grade) dysplasia
- Invasive adenocarcinoma
Describe low grade dysplasia
- Cells polarised
* nuclei stratified
Describe high grade dysplasia
- Polarity lost
- Nuclei rounder
- Vesicular
- Prominent nuclei
- Abnormal mitoses
- Necrosis
What are the causes of acute gastritis in the stomach?
- Alcohol
- NSAIDs
- Severe trauma (burns, surgery)
What are the causes of chronic gastritis?
- Autoimmune
- Bacterial (H pylori)
- Chemical
Explain how autoimmune atrophic gastritis causes anaemia
- Parietal cells that release intrinsic factor are targeted by anti-parietal cell antibodies in the blood
- Intrinsic factor binds to vitamin B12 in the duodenum once hepatocorrin has been digested
- B12 is needed for haumatopoeisis, lack of B12 results in pernicious anaemia
- Eventual complete loss of parietal cells, pyloric and intestinal metaplasia
What are the complications of autoimmune gastritis?
- Achlorhydria results in bacterial overgrowth
- Hypergastrinaemia (more gastrin) leads to endocrine cell hyperplasia/carcinoids
- Persistent inflammation may lead to epithelial dysplasia and eventually cancer
What is Zollinger-Ellison syndrome?
Hypersecretion of gastrin by an endocrine tumour in the pancreas or the duodenum resulting in increased gastric acid output and severe peptic ulceration
Discuss helicobacter pylori gastritis
- Potentially lifelong
- H. pylori colonies the gastric mucosa leading to active chronic inflammation
- IL- 8 from epithelial cells attracts neutrophils
- There are two patterns
What are the two patterns of helicobacter pylori gastritis?
- Antral-predominant gastritis - hypergastrinaemia and duodenal ulceration
- Pan-gastritis- hypochlorhydria, multifocal atrophic gastritis, cancer, intestinal metaplasia
What are the causes of a chemical gastritis?
- Bile reflux
- NSAIDs
- Ethanol
- Oral iron
What is the characteristic morphology of chemical gastritis?
- Few inflammatory cells
- Surface congestion oedema
- Elongation of gastric pits
- Tortuosity
- Reactive hyperplasia/atypia
- Ulceration
What is gastric cancer associated with?
- Helicobacter pylori
* Autoimmune
What are the features of gastric cancer?
- Background atrophic mucosa
- Chronic inflammation
- Intestinal metaplasia
- Dysplasia
What is the Lauren classification of gastric cancer?
- Intestinal
* Diffuse
What is the most common cause of proximal gastric cancer?
Acid reflux at the OG junction
What is the most common cause of distal gastric cancer
Mainly helicobacter pylori infection or autoimmune
Describe the histology of diffuse gastric cancer
- Signet ring cells: individual malignant cells with mucin vacuoles
- Linitis plastica (adenocarcinoma of the stomach): may invade extensively i.e. to muscles without being endoscopically obvious
- weaker link with gastritis
Where are the most likely points of metastasis from gastric cancer?
- Ovaries - krukenberg tumour
- Supraclavicular lymph node (Virchow’s)
- Sister Joseph’s nodule (umbilical metastasis)
What is the associated mutation in familial gastric cancer?
CDH1 - E-cadherin
Describe the risk of familial gastric cancer
- Penetrance is 70-80% (lifelong)
- Small intramucosal foci or diffuse gastric cancer may be numerous
- Prophylactic gastrectomy
- Increased risk of lobular carcinoma of the breast
