Histopathology 11: Upper G.I pathology Flashcards
In which part of the stomach does H.Pylori tend to reside ?
Pyloric antrum and pyloric canal
List the 3 layers of tissue seen on histology of the antrum and body of the stomach ?
- gastric mucos collomnar epithelium at the top
- Lamina propria in the middle (with specialised acid secreting glands)
- Muscularis mucosa at the bottom
What is the normal villous: Crypt ratio in the duodenum ?
villous: crypt > 2:1
What do goblet cells in the stomach suggest ?
Metaplasia - should not be any goblet cells in the stomach
Which risk factors are associated with squamous cell carcinoma of the oesophagus ?
- -Smoking and alcohol
- -More common in afro-carribeans
Which risk factors are associated with adenocarcinoma of the oesophagus ?
- Barret’s oesophagus
- GORD
- smoking
- obesity
Which cancer is more common in the distal 1/3 of the oesophagus ?
Adenocarcinoma
Which cancer is more common in the middle 1/3 of the oesophagus ?
Squamous cell carcinoma
List 3 causes of acute gastritis (inflammation of gastric mucosa)?
- NSAIDS
- Alcohol
- H.Pylori
List 3 causes of chronic gastritis ?
ABC of gastritis:
- Autoimmune: anti-parietal autoantibodies
- Bacterial: H. pylori
- Chemical: NSAIDs, bile reflux
Key cells in chronic = lymphocytes
What does the presence of lymphoid follicles (MALT) in the stomach suggest ?
- H.Pylori infection
- Increased risk of lymphoma (gastric MALToma)
Which type of cancer is most common in the stomach ?
Adenocarcinoma
what is the z-line in the oesophagus
point at which epithelium transitions from squamous to columnar (squamo-columnar junction)
Oesophagus = squamous, stomach = columnar
important feature of the oesophageal mucosa
submucosal glands
marker for intestinal type epithelium
glandular epithelium with goblet cells
hallmark of acute inflammation in general
Neutrophil polymorphs
Commonest cause of oesophagitis
Reflux Oesophagitis/ GORD
Aetiology of Barrett’s oesophagus
Two types
- NORMAL squamous epithelium of the lower oesophagus is REPLACED by metaplastic columnar epithelium (usually with goblet cells)
- Due to GORD/reflux
- WITHOUT goblet cells - gastric metaplasia
- WITH goblet cells – intestinal type metaplasia (NB since no goblet cells in gastric/stomach, but there are in intestine)
Is cancer more likely in gastric metaplasia (without goblet cells) or intestinal metaplasia (with goblet cells) in Barrett’s oesophagus?
MUCH HIGHER in intestinal metaplasia
Premalignant stages before cancer
Metaplasia (reversible) > dysplasia > cancer
How do cells in Barrett’s look during screening for the disease?
hyperchromatic
Most common type of oesophageal cancer in developed countries
Most common WW
- Adenocarcinoma of the Oesophagus (associated with reflux)
- Adenocarcinomas form glands and secrete mucus
- Found in lower oesophagus
WW: Squamous Cell Carcinoma (mid-lower oesophagus)
Most damaging form of H pylori
- Cag-A +ve H. pylori
- Cag A is a toxin
- Switches off apoptosis in gastric cells and so damaged cells are not killed, so DNA damage in cells persists
commonest opportunistic viral infection to cause gastritis
CMV
Which IBD can cause gastritis
Crohn’s
What is metaplasia and is it reversible?
Metaplasia is a change from one cell type to another and by definition is reversible - NOT precancerous
What is dysplasia?
Some of the cytological and histological features of malignancy are present, but NO invasion through the basement membrane, so no chance of metastasis
Features of malignancy:
- Big nuclei
- Raised nucleocytoplasmic ratio
- Increased mitoses
- Abnormal mitoses
Infection that is major RF of gastric cancer
H. pylori
>95% of all malignant tumours in the stomach are what type?
ADENOCARCINOMAS
- Can get well differentiated
- or poorly differentiated: Linitis plastica, signet ring cell carcinoma
Signet ring cells seen in which type of GI cancer?
poorly differentiated adenocarcinoma of gastric cancer
Cause of ALMOST ALL duodenal ulcers
- H. pylori
- NB also cause of half gastric cancers
- stimulates increased acid secretion which spills over the stomach and into the duodenum and induces acute duodenitis
Pain in duodenal ulcer made worse/relieved by food?
Relieved
NB most of these ulcrs due to H pylori
Very common parasite which exists in immunocompetent people and can affect duodenum
Another disease affecting duodenum
Giardia lablia infection
Whipple’s disease
Histological changes in Malabsorption Partial Villous Atrophy (like in Coeliac)
- Villous atrophy- become smaller
- Crypt hyperplasia- become bigger
- Increased intraepithelial lymphocytes
Rule on food if wanting to do duodenal biopsy for Coeliac
Stay on gluten diet otherwise won’t see villous atrophy with increased intraepithelial lymphocytes
Those with coeliac are more likely to develop which malignancy?
increased risk of GIT cancers: MALToma
AKA Enteropathy associated T-cell Lymphoma (EATL)
NB lymphomas in the stomach due to H. pylori are B cell lymphomas
Does food help/worsen Sx of gastric ulcer?
WORSEN
How invasive is gastric ulcer?
Link between gastric ulcer and cancer
defect goes THROUGH the muscularis mucosae (through the full thickness of the mucosa and into the submucosa)
- Ulcers may become malignant, but cancers may also ulcerate
- ALL ULCERS SHOULD BE BIOPSIED TO EXCLUDE MALIGNANCY
