The cells of origin of GIST is:
|C||Interstitial cell of Cajal|
|D||Smooth muscle cell|
a. GIST are the most common mesenchymal tumors of the GIT>
b. GIST are thought to arise from a pacemaker cell within the gastrointestinal tract known as the interstitial cell of Cajal.
c. These cells GIST cells express the hematopoietic progenitor cells marker CD-34 & growth factor receptor C-KIT.
d. The interstitial celll of the cajal is mesodermally derived cell located in the wall of GIT. It functions Dr.A.Sanap MS(Ortho) a pacemaker in the transmission of the stimuli leading to the co-ordinated contraction of the smooth muscle.
e. GIST was given a name of Gastrointestinal pacemaker cell tumor.
f. CD117 is normally expressed by these cells.
g. CD117 positivity is considered diagnostic of the GIST.
h. Membrane positivity of CD117 is more convincing feature of diagnosis of GIST.clinically gist occur in adults patients usually presents with abdominal pain and melena.
i. The malignat GIST do metastasize.
j. The common sites of the metastasis of GIST are liver, peritoneum and lungs.
k. Risk categories and prognosis of GIST depends upon size of the tumor and mitotic counts.
l. The GIST are divided Dr.A.Sanap MS(Ortho) very low risk, low risk , intermediate, and high risk GISTs.
m. GIST may show neural differentiation so called GANTs and epithelioid differentiation.