GI Pathology Flashcards
How long is the oesophagus?
25cm
What type of epithelium lines the oesophagus?
Squamous epithelium
What is the name of the spinchter at the upper and lower end of the oesophagus?
Cricopharyngeal sphincter
Gastro-oesophageal sphincter
What type of epithelium lines the distal 2cm below the diaphragm?
Glandular (columnar) mucosa
The squamo-columnar junction is usually located at ___cm frm the incisor teeth
40cm
Reflux of gastric acid
gastro-oesophageal reflux
Reflux of gastric acid and/or bile
Duodeno-gastric reflux
2 types of hernia
Sliding hiatus hernia
Para-oesophageal hernia
What is a serious complication of para-oesophageal hernias?
Strangulation
What 3 histological changes occur in the squamous epithlium during reflex oesophagitis?
Basal cell hyperplasia
Elongation of papillae
Increase in cell desquamation
How might a benign stricture in reflux oesophagitis present?
Dysphagia
Risk factors for barrett’s oesophagus
Male, caucasian, overweight
Define barrett’s oesophagus in macroscopic terms
Proximal extention of squamo-columnar junction- squamous mucosa replaced by columnar mucosa (glandular metaplasia)
What are the 3 types of columnar mucosa in the GI tract
Gastric cardia type
Gastric body type
Intestinal type ‘specialised barrett’s oesophagu’
What are the 2 histological types of oesophageal carcinoma?
Squamous cell carcinoma
Adenocarcinoma
Risk factors for adenocarcinoma
Mle, caucasian, obestiy, Barrett’s oesophagus, tobacco
What are the 3 types of oesophageal adenocarcinoma
Polypoidal
Stricturing
Ulcerated
A tumour that projects into the lumen of the oesophagus
Polypoidal
Risk factors for squamous carcinoma
Tobacco, alcohol, nutrition, thermal injury, HPV, male, black ethnicity
Location of oesophageal adenocarcinoma
lower oesophagus
Location of squamous carcinoma
Middle and lower 1/3rd
Tumour invades lamina propria, muscularis mucosae or submucosa
PT1
Tumour invades muscularis propria
PT2
Tumour invades adventitia
PT3
Tumour invades adjacent structures
PT4
No lymph node metastasis
PN0
Metastasises to 1 or 2 nodes
PN1
Metastasises to 3-6 nodes
PN2
Metastasises to 7 or more lymph nodes
PN3
No distant metastasis
MO
Distant metastases
M1
4 anatomical regions of the normal stomach
Cardia
Fundus
Body
Antrum
3 histological regions of the stomach and the type of glands found in each
Cardia-mucinous glands
Body-specialised glands
Antrum-mucinous glands
Types of chronic gastritis
ABC Autoimmune (glandular atrophy) Bacterial infection e.g. H.Pylori Chemical injury (foveolar hyperplasia) (NSAIDs, Bile reflux, alcohol)
How does bile reflux present histologically
Degranulation of mast cells- vasodilation
How does overuse of NSAIDs present histologically
Disruption of mucous layer- oedema
Describe the shape and type of H.Pylori
Gram -ve spiral shaped bacterium with flagellae
Which part of the stomach is H.Pylori more common?
Antrum
Result of H.Pylori infection in the stomach
Glandular atrophy, replacement fibrosis and intestinal metaplasia
Complications of H.Pylori
85% no symptoms
Gastric or duodenal (more common) ulcer
Gastric cancer (usually adenocarcinoma)
MALT lymphoma (mucosa associated lymphoid tissue)
Major sites for peptic ulcer disease
Junction of antral and body mucosa
First part of duodenum
Distal oesophagus
Risk factors for peptic ulcer disease
Hyperacidity H.Pylori infection duodeno-gastric reflux Drugs (NSAIDS) Smoking
Full thickness coagulative necrosis of mucosa (or deeper layers) covered with ulcer slough (necrotic debris and fibrin and neutrophils) Granulation tissue at ulcer floor
Peptic Ulcer Disease
Difference between peptic ulcer disease and chronic gastric ulcer?
Chronic gastric ulcer- clear cut edges overhanging the base. Extensive graulation and scar tissue at ulcer floor.
Complications of chronic gastric ulcer
Haemorrhage (–>anaemia)
Perforation (–>peritonitis)
Stricturing
What is more common- gastric or duodenal ulcer?
Duodenal
Which type of ulcer is more common in older patients?
Gastric
Which type of ulcer is more common in people with blood group A?
Gastric
Which type of ulcer is more common in people with blood group O?
Duodenal
What are the different types of gastric cancer?
Adenocarcinoma (most common)
Endocrine tumours
MALT lymphomas
Stromal tumours (GIST)
Risk factors for gastric adenocarcinoma?
Diet (smoked/cured meats) H.Pylori Bile Reflux Hypochlorhydria (low HCl concentration- allows bacterial growth) Mutation in E.cadherin gene
Is there an asoociation between H. pylori/diet and carcinoma of gastro-oesophageal junction?
no
Is there an asoociation between H. pylori/diet and carcinoma of gastric body/antrum?
yes
Is there an asoociation between GO reflux and carcinoma of gastro-oesophageal junction?
yes
Is there an asoociation between GO reflux and carcinoma of gastric body/antrum?
no
A gastric carcinoma that
a) bulges out of the epithlium
b) Neither bulges out or is depressed within
c) Depressed within epithelium
Exophytic
Flat/depressed
Excavated
Diffuse type gastric carcinoma is a result of what mutation?
E.cadherin loss/mutation
What type of cells is characteristic of diffuse type gastric cancer?
Signet ring shape cells.
Cells infiltrate widely-marked thickening of the wall
Linitis plastica
What type of gastric cancer arises from a germline CDH1/E.Cadherin mutation?
Hereditory diffuse type gastric cancer (HDGC)
What is the coeliac disease producing component and what effect does it have on the epithelial cells of the intestines?
Gliadin, induces epithelial cells to express IL-15 which activates CD8 and intraepithelial lymphocytes (IELs) which are cytotoxic and kill enterocytes. Net results is atrophy of villi, mucosa flattens and malabsorption sundrome
Positive serology for coealiac disease and villous atrophy but no symptoms
Silent disease
Positive serology for coealiac disease, no villous atrophy
Latent disease
Clinical features of coeliac disease
Anaemia, chronic diarrhoea, bloating, chronic fatigue
Disease associations with coeliac disease
Dermatitis herpetiformis
Lymphocytic gastritis and colitis
Enteropathy-associated T cell lymphoma
