GIST

Question 1

Q1. what is jaundice ?

Answer 1

Clinical condition chch by yellow discoloration of skin and mucous membranes due to elevated bilirubin above the normal levels

Question 2

Q2. why patient with GIST might present with jaundice ?

Answer 2

As the tumor may be large enough to compress on biliary tree and increase the levels of bilirubin

Question 3

Q3.What is GIST?

Answer 3

One of the paraynchymal tumors of GI tract and comes from interstitial cells of Cajal which are autonomic cells of GIT

Question 4

Q4.How does it differ from gastric carcinoma?

Answer 4

It is arising from CT and not epithelial
-Type of cells are interstitial cells of Cajal not the epithelial lining
- LN Mets are not common
- Have distant spread to liver, omentum, mesentery

Question 5

Q5.Clinical presentation?
GIST

Answer 5

Can be asymptomatic (10%) but most of the pt can have N,V abd discomfort, Bleeding and dysphagia and jaundice and intssusption

Question 6

Q6.Patient presented with jaundice few months later. Why ?

Answer 6

2ry mets to liver / drug induced (imitanib)

Question 7

Q7. Function of bile?

Answer 7

Enhancing absorption of fat/ bacteriostatic effect on GIT

Question 8

Q8: How does bile salts help in emulsification of fat?

Answer 8

Bile salts assist in the emulsification of fat by surrounding lipid droplets (such as triglycerides and phospholipids) to form micelles. Their hydrophilic (water-attracting) sides face outward, while their hydrophobic (water-repelling) sides face inward towards the fat. This arrangement stabilizes the fat droplets and prevents them from re-aggregating into larger particles, allowing for more efficient digestion and absorption of fats.

Question 9

Q9.What is bilirubin conjugated to?

Answer 9

Glucuronic acid

Question 10

Q10: Bilirubin metabolism?

Answer 10

Conjugated bilirubin is excreted into the bile and then into the small intestine.
While most bile acids are reabsorbed in the terminal ileum for enterohepatic circulation, conjugated bilirubin continues to the colon.
There, colonic bacteria convert it into colorless urobilinogen, which can be further oxidized to form stercobilin, giving stool its brown color.
About 10% of urobilinogen is reabsorbed into the enterohepatic circulation and re-excreted in the bile, with some processed by the kidneys, resulting in yellow-colored urine.

Question 11

Q12.A mass had been found, how to diagnose it?
GIST station

Answer 11

US / Ct with contrast / Upper Gi endo biopsy for IHC to show Tumor marker CD117 / CD34

Question 12

Q13:What is CD117? How to detect it?

Answer 12

Protoncogene also know as tyrosine protein kinase

Question 13

Q14.What Other cells that show CD117 positive ?

Answer 13

Mast cells

Question 14

Q15.Management?
GIST

Answer 14

According the severity
Mild (Small – Asymptomtic) – > conserve mang with surveillance at 6m-12m
Symptomatic – > complete surgical resection
we also consider Imatinib taking orally as adjuvant ttt

Question 15

Q16.What is the value of CD 117 in treatment?

Answer 15

Will show us weather the tumor will respond to imatinib (overexpressed) or not.

Question 16

Q17: what is H .pylori ? Which part of stomach usually affected ?

Answer 16

One of normal flora of stomach G-ve flagellated and present at the antrum

Question 17

Q18. What cancer other than adenoma does H. pylori cause?

Answer 17

MALToma

Question 18

Q19: Cause of vit b 12 deficiency ?

Answer 18

Pernicious anemia/ Post-gastrectomy /Obst. Jaundice

Question 19

Q20 other causes of macrocytosis ?

Answer 19

Folic acid defficency
Alcohol
Drugs
Antipsychotics