GI Neoplasia III Flashcards
Put parietal cells, chief cells, and neuroendocrine cells in order of appearance from the bottom of a gastric gland to the top
Neuroendocrine cells are deepest in the gastric gland—- then Chief cells—-then Parietal cells near the top
What do parietal cells secrete ?
acid
What do chief cells secrete
Pepsin
Pathophysiology of carcinoid tumor
Chronic gastritis or gastric acid suppression can lead to hypergastrinemia (high gastrin levels trying to stimulate more acid release)
This in turn can lead to gastric diffuse neuroendocrine hyperplasia which can develop into a gastric carcinoid tumor
What stains are used to insure that a tumor is neuroendocrine in nature?
CHROMOGRANIN and somatrophysin
What is type I carcinoid syndrome?
Tumor is associated with hypergastrinemia, usuallyindolent (slow growing), and mets are very uncommon
What is type II carcinoid syndrome?
Tumor is associated with high gastrin levels that are coming from outside the stomach (usually a pancreatic tumor or something of that sort). Treat the carcinoid syndrome but also treat the tumor
Type III carcinoid syndrome?
Not associated with hypergastrinemia, very aggressive, many with metastases at diagnosis, assoc with carcinoid syndrome
ANd what does carcinoid syndrome look like
bunch of nodules in the fundus of the stomach
What are the possible ways to treat a type 1 carcinoid tumor?
- take out the nodules
- take out the antrum of the stomach where the gastrin is coming from
Zollinger Ellison Syndrome
High levels of gastrin due to a gastrin secreting tumor in the pancreas or small intestine usually.
Diagnosis made bby gastrin level over 1,000 with gastrin pH below 5
Treatment of zollinger-ellison syndrome
- surgical resection
- High dose PPI
- Long acting somatostatin analog
Outside of the stomach, what is the most common site of a carcinoid tumor
small bowel
Where in the small intestine do carcinoid tumors generally appear?
Illeum and appendix
What age range for intestinal carcinoid tumors
late middle age
most common symptom of intestinal carcinoid tumor?
abdominal pain
Carcinoid syndrome is characterized by
bronchospasm, diarrhea, flushing of skin
Carcinoid heart disease
right hear endocardial fibrosis
What kind of carcinoid tumors generally lead to carcinoid syndrome?
carcinoid tumors in the ileum that have liver mets
What causes carcinoid syndrome symptoms
vasoactive polypeptides and serotonin levels
What test is diagnostic?
High urine 5-hydroxyindole acetic acid
Colorectal neuroendocrine umors most commonly seen where
right colon, usually a large mass
Gastrointestinal stromal tumor generally presents in what way
incidental finding….unless they are symptomatic (i.e have black tarry stool)
Gastrointestinal stromal tumors most common where?
stomach and small intestine
GIST derive from what?
Cells of cajal, GI pacemaker cells that form the interface between autonomic innervation and smooth muscle cells of the gut
GIST stains positive for
CD117
Most GISTs have a mutation in what?
KIT transmembrane receptor
DXof GIST
CT detects them but be careful with endoscopy because it may come back false negative since they are in the wall and not the mucosa
Endoscopic ultrasound guided fine needle aspiration is best test
Post- transplant lymphoproliferative disorder?
Immunosuppresion allows B cells with EBV to proliferate in an uncontrolled manner
DX of PTLD
blood test for EBV DNA
GI lymphoma
70% in stomach
look at GI lymphoma stuff
ok
