Chapter 40: Stomach- GIST Flashcards
1
Q
What is it?
A
GatroIntestinal Stromal Tumor
2
Q
What was it previously known as?
A
Leiomyosarcoma
3
Q
What is the cell of origin?
A
CAJAL, interstitial cells of Cajal
4
Q
Where is it found?
A
GI tract—“esophagus to rectum”
- most commonly found in stomach (60%)
- small bowel (30%)
- duodenum (5%)
- rectum (3%)
- colon (2%)
- esophagus (1%)
5
Q
What are the symptoms?
A
- GI bleed
- occult GI bleed
- abdominal pain
- abdominal mass
- nausea
- distention
6
Q
How is it diagnosed?
A
- CT scan
- EGD
- colonoscopy
7
Q
How are distant metastases diagnosed?
A
PET
8
Q
What is the tumor marker?
A
C-KIT (CD117 antigen)
9
Q
What is the prognosis?
A
Local spread, distant metastases
Poor long-term prognosis: size >5 cm, mitotic rate >5 per 50 hpf (high-powerfield)
10
Q
What is the treatment?
A
Resect with negative margins, ± chemotherapy
11
Q
Is there a need for lymph node dissection?
A
NO
12
Q
What is the chemotherapy for metastatic or advanced disease?
A
Imatinib—tyrosine kinase inhibitor
