GIST Support International - Glossary of Terms
| Definition |
| ileum | The lowest section of the small intestine, connecting to the colon (large intestine). |
| immunohistochemical | Relating to the staining of tissue samples using antibodies. |
| in situ | In place, referring to an unresected tumor still in its site of origin in the body, without invasion or metastasis to other locations. |
| Interstitial cells of Cajal (ICCs) | ICCs are cells found in the myenteric plexus and nearby areas between the circular and longitudinal layers of the gastrointestinal tract. Their function is to regulate gastrointestinal motility, or peristalsis, which is the autonomic movement of the GI tract to propel food through the system. The ICCs initiate and propagate the slow wave activity of gastrointestinal wall muscles. Either ICCs, or the more primitive cells that give rise to ICCs, are the source of gastrointestinal stromal tumors. |
| intramural | "Within the wall," referring to the wall of the gastrointestinal tract. GISTs begin their development in the layer of the GI tract wall between the circular and longitudinal muscle layers, and a very small GIST may still be contained intramurally. Eventually most GISTs grow outward, breaking through the muscle layer. |
