Stomach 2 Flashcards
Hereditary diffuse gastric cancer is an inherited form of gastric CA, caused by what mutation?
E-cadherin mutation
***80% of these pts will develop gastric CA
Li Fraumeni syndrome is an AD syndrome caused by mutation what gene?
p53
**have risk of many malignancies, including gastric Ca
Hereditary non-polyposis colorectal cancer is AKA?
lynch syndrome
Lynch syndrome is a mutation in what?
assc w/ microsatellite instability
**also assc w/ increased risk of ovarian + gastric Ca
What is a micro-satellite?
lengths of DNA where 1 to 5 nucleotides motifs are repeated several times
What are some genes over-expressed in gastric Ca?
c-met
k-sam
c-erbB2
Pts with pernicious anemia are at increased risk of gastric Ca, what’s the defining feature of this dx?
achlorhydria
chief and parietal cells are destroyed by an autoimmune response
MOA of PPIs?
block H-K pump within the parietal cell
block all acid secretion in the stomach
***as a result pts develop hyper-gastrinemia
Few classification systems used to characterize gastric Ca?
Bormann classification–> uses macroscopic appearance, V types
Lauren classification–> separates gastric Ca into intestinal vs. diffuse type
What are some features of intestinal type gastric Ca?
arises in setting of a pre-cancerous condition; like gastric atrophy and intestinal metaplasia
M>W
incidence increases with age
mets via hematogenous spread
environmental causes involved
What are some features of diffuse type gastric Ca?
poorly differentiated, lacks glands
has tiny clusters of signet ring cells
W>M
younger age group affected
assc. w/blood type A
Diffuse type gastric Ca associated with what blood type?
type A
Better prognosis with intestinal or diffuse type gastric Ca?
intestinal type gastric Ca
Supraclavicular mets of gastric Ca called what?
Virchow’s nodes
What are Virchow’s nodes?
gastric Ca that has mets to supraclavicular nodes
What is a Sister Mary Joseph node?
gastric Ca that has mets to peri-umbilical area
Gastric Ca drop mets to ovaries called what?
Krukenberg tumors
Peritoneal gastric Ca mets felt on rectal exam called what?
Bloomer’s shelf
Most widely used staging system for gastric Ca?
TNM
In the TNM staging system for gastric Ca, how many nodes needs to be evaluated?
15
What’s the number of nodes that need to be evaluated in gastric Ca?
15
For gastric cancers of distal stomach, including the body and antrum, what operation do we perform?
distal gastrectomy
*distal margin should be proximal duodenum
frozen section should be performed prior to reconstruction
can do Bilroth I vs II
When performing gastrectomies for gastric Ca, how wide of a margin do we want?
at least 6 cm
studies have shown tumor spread as far as 5 cm
What surgery do we perform for proximal gastric Ca?
total gastrectomy w/Roux-en-y w/esophagojejunostomy
When do we perform endoscopic resection of early gastric Ca?
tumor is limited to the mucosa
there is NO lymphovascular invasion
tumor is smaller than 2 cm
there are no ulcers
Most recurrences of gastric cancer occur within what time frame?
3 yrs
Where does gastric Ca tend to spread to?
liver, lung, bone
MOst common site of lymphomas in the GI system>
stomach
Where do we see lymphomas most commonly in the GI system?
stomach
Share some facts about gastric lymphomas:
occur in older pts (6-7th decade)
M>F
usually occur in antrum
50% of pts will present with anemia
M0st common gastric lymphoma?
diffuse large B cell lymphoma (55%)
Most common gastric lymphomas?
diffuse large B cell (55%)
gastric MALT lymphoma (40%)
Burkitt’s lymphoma (3%)
mantle cell and follicular lymphoma (1%)
Risk factors for development of diffuse large B cell lymphoma??
h. pylori
immunodeficiencies
Burkitt’s lymphoma of stomach associated with what?
Epstein-barr virus
This type of gastric lymphoma is very aggressive, tends to affect younger pts, usually found in cardia of stomach;
Burkitt’s lymphoma
Tx for gastric lymphoma?
surgery controversial
most treated w/chemotherapy alone
Most common chemotherapy regimen for gastric lymphoma is?
CHOP
cyclophosphamide
doxorubicin
vincristine
prednisone
When is surgery for gastric lymphoma performed?
pts w/limited gastric disease
pts w/recurrence of treatment failure
pts w/complications like bleeding, obstruction, perforation
Gastric MALT lymphoma is usually preceded by what?
h-pylori associated gastritis