Comprehensive review (2) Flashcards
Chronic, most often solitary lesions that occur in any portion of the GI tract exposed to the aggressive actions of acid/peptic juices, often <4 cm
Peptic ulcers
Histologic definition of peptic ulcer: a breach in the mucosa that penetrates the _______; may penetrate gastric wall
muscularis mucosa
more common location of peptic ulcers
- Duodenum, first part
- Stomach, usually antrum
- Within Barrett mucosa
Most frequent complication of ulcers
Bleeding • Most frequent complication • Occurs in 15-20% of patients • May be life-threatening • Accounts for 25% of ulcer deaths • May be first indication of an ulcer
Is perforation common in ulcers?
rare but accounts for 70% of ulcer
complication of ulcers located in pyloric channel
obstruction from edema or scarring
When do we see acute gastric ulceration?
stress, shock, burns, trauma, NSAIDS
Pathogenesis of acute gastric ulceration:
stimulation of vagal nuclei and secretion of acid, prostaglandin inhibition, decreased oxygenation,
Can manifest as ulcers or erosions
• Discrete lesions with no surrounding gastritis, no chronic scarring
Acute gastric ulceration
treatment for acute gastric ulceration
fix the cause
concretions formed in the alimentary canal
bezoar
• Acute gastritis • Gastric varicies • Mallory Weiss syndrome: mucosal tear to due to severe retching These can all lead to:
Gastric hemorrhage; can be asyptomtatic to life threatening
Massive hyperplasia of surface mucous cells
Menetrier disease (type of hypertrophic gastropathy)
Hyperplasia of parietal and chief cells
Hypertrophic-hypersecretory gastropathy
Gastric gland hyperplasia due to excessive gastrin secretion
Setting of gastrinoma: Zollinger-Ellison syndrome (type of hypertrophic gastropathy)
Caused by gastrin-secreting
tumors, gastrinomas
ZE syndrome
What is in the gastrinoma triange?
duodenal wall
peripancreatic soft tissue
pancreas
How do pts with ZE syndrome present?
- Patients often present with duodenal ulcers, GERD, or chronic diarrhea
- 90% of ZE patients have peptic ulcers
- Proximal dudodenum or unusual locations (distal duodenum, jejunum)
effect of ZE syndrome on stomach
doubling of oxyntic mucosal thickness
fivefold increase in the number of parietal cells
induces hyperplasia of mucous neck cells, mucin hyperproduction, and proliferation of endocrine
cells
Gastrin
Tx of ZE syndrome
• TX includes blockade of acid hypersecretion
proton pump inhibitors
high-dose H 2 histamine receptor antagonists
Peptic ulcers to heal and prevents gastric perforation
Allows treatment to focus on the gastrinoma, which becomes the main determinant of long-term survival
Gastrinoma: Grow slowly
• 60% to 90% are____
• 75% Gastrinoma is____ (40-50 yo)
malignant
sporadic
solitary gastrinoma tumors can be:
surgically resected
represent 75% of gastrinoma
seen in 40-50 yo
• 25% of gastrinomas are: Multiple endocrine neoplasia type I (MEN I) (20-30)
Usually multiple tumors or metastatic disease and seen assoicated with what else?
“PPP” Pituitary Andenoma (<40y/o)
What may GAstrinomas respond to SST analogues
Gastrinoma cells contain type 2 somatostatin receptors that bind somatostatin analogues (octreotide) with high affinity
• All patients with gastrinoma have an
elevated
gastrin level
Hypergastrinemia in the presence of
elevated acid production strongly suggests
gastrinoma
how must we rule out MEN1 if we suspect gastrinomas?
measure serum Ca and parathyroid hormone
Cells that stain with chromagranin are suggestive of:
hypergastrinemia( d/t increased gastrin secreation from chronic PPI use)
nodule or mass projecting above the mucosa and uncommon in stomach
Polyps
Majority of polyps are______(inflammatory
or hyperplastic), most frequently
associated with ______
non-neoplastic
chronic gastritis
proliferative gastric mucosa with acute and chronic inflammatory infiltrates in lamina propria, often multiple
Hyperplastic polyps
contains proliferative dysplastic epithelium, therefore potential for malignant transformation, usually single
Adenoma
What do we do to polpys?
remove them
majority of malignant gastric tumors are
Carcinomas(90-95%)… specifically adenocarcinomas
Leading world-wide cause of cancer death
• 2 nd most common tumor in the world
Gastric carcinoma
***US has declined dramaticallY
Which type of gastric carcinoma?
• Associated with defined risk factors
• Develops from precursor lesions
• 6 th decade, males>females
Intestinal
Which type of gastric carcinoma?
• Relatively constant incidence with no
known precursor lesion
• 5 th decade, males=females
Diffuse
Risks: environmental for Gastric Carcinoma
• Diet
Nitrites (from nitrates in water, preserved food)
Smoked & salted food, pickled vegetables
Lack of fresh fruit & vegetables
• Cigarette smoking
• Low socioeconomic status
• Infection by H. pylori
What cancer is H.pylori factor for?
intestinal type carcioma and MALToma
Shit about H.pylori
- H. pylori causes gastritis
- Untreated gastritis is a risk factor for gastric cancer
- Infection increases risk 5-6x
- Prospective epidemiologic studies
- Geographic and socioeconomic association
People with chronic gastritsi have what risk factors?
– Hypochlorhydria (favors H. pylori colonization)
– Intestinal metaplasia: precursor lesion for CA
– Setting for development of gastric adenomas
How are gastric adenomas correlated to risk for cancer in host?
• Gastric adenomas
– 40% harbor carcinoma at time of diagnosis
– 30% have adjacent carcinoma
How is Barretts a risk for gastric carcinioma?
• Barrett esophagus
– Increased incidence of cancer at GEJ
How do we determine prognosis of Gastric Carcinoma?
• Depth of invasion the most important
factor, then lymph node involvement,
metastasis; histology not as important
Prognosis of Gastric Carcinoma if found early and its confined
If early (confined to mucosa, submucosa), 5-year survival 90-95%
good prognosis even with + local lymph nodes
Prognosos if carcinoma found later?
Advanced (into muscularis propria): <15% fiveyear survival
