The concept of gastrointestinal stromal tumors (GIST) was first put forward by Mazur and Clark in 1983 to distinguish a group of gastrointestinal tumors that are neither smooth muscle nor neurogenic. GIST is defined as all gastrointestinal spindle cell tumors with unknown biological behavior and origin. In 1998, Kindblon and other studies showed that GIST was similar to Cajal cells around the myenteric plexus of gastrointestinal tract, with positive expression of c-kit gene, CD117 and CD34. ICC is a gastrointestinal pacemaker cell, so some people call it gastrointestinal pacemaker cell tumor (GIPACT). However, GIST can occur outside the gastrointestinal tract, such as omentum and mesentery, and GIST tumor cells have no ICC function, so at present, it is thought that GIST may not originate from ICC, but from precursor cells (mesenchymal stem cells) homologous to ICC, which may also explain the expression of focal myogenic markers in some tumor cells.

immunohistochemical study of p>GISTs showed that CD117(c-kit) and CD34 were important markers. 8 ~ 1% of GISTs CD117 was diffusely expressed, while smooth muscle cells and nerve fibers did not express CD117. In 6 ~ 8% of GISTs tumor cells, CD34 was diffusely positive, and the expression of CD34 in benign GISTs was higher. The expression of CD34 is specific, which is of great value in distinguishing GIST s from leiomyomas or neurogenic tumors.