[Gastrointestinal stromal tumors: conceptual evolution].

Gastrointestinal stromal tumors (GISTs) constitute the largest category of primary nonepithelial neoplasms of the stomach and small bowel. They represent about 1-2% from all neoplasms of the digestive tract. They occur most commonly in the stomach and small bowel, but small series of comparable tumors have also been reported in all the other parts of the tubular gastrointestinal tract, including esophagus, colon, rectum and anus. They can also involve omentum, mesentery, uterus, retroperitoneum, mesocolon and soft tissues. Originally recognized in 1960 by Martin et. al. as a distinctive type of stromal neoplasm of the bowel, they were subsequently reported by Stout, who introduced the term leiomyoblastoma. Because of difficulties in accurately predicting the biologic behavior of these tumors, the term "smooth muscle tumor of uncertain malignant potential" (SMTUMP) has been introduced for borderline tumors. In 1983, Mazur and Clark coined the term gastrointestinal stromal tumor and suggested that these neoplasms might arise from the myenteric nervous system. Some studies have reported evidence of neuronal cell differentiation in a proportion of GISTs and the term "gastrointestinal autonomic nerve tumor (GANT) has been introduced. Kindblom et al are providing cogent arguments to suggest that GISTs show differentiation toward interstitial Cajal cells (pacemaker cells of the gastrointestinal tract). Inmunohistochemically the GISTs often reveal inmunoreactivity for vimentin. CD34 and CD 117. The aim of this paper is to perform and analysis of the historic evolution and conceptual of the GISTs.