RESUMEN
Although gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract, it also occurs in the non-gastrointestinal tract, and is referred to as extragastrointestinal stromal tumor (EGIST). In this report, we describe a 48-year-old female patient who presented with hematuria, and who was finally diagnosed with a primary extragastrointestinal stromal tumor of the pelvic cavity involving the bladder, vagina and left ureter. Tumor cells were positive for immunohistochemical staining for CD117 antigen (proto-oncogene protein c-kit), CD34, and vimentin, whereas they were negative for desmin, smooth muscle actin, and S-100 protein. These findings provide histopathological and immunohistochemical evidence for diagnosing this tumor as EGIST.