Gastrointestinal stromal tumors mimicking gynecological masses on ultrasound: a report of two cases.

Gastrointestinal stromal tumors (GISTs) are among the most common mesenchymal tumors of the gastrointestinal tract. Diagnosis of GIST on ultrasound examination can be difficult because of their similarity in appearance to gynecological neoplasms. We present two cases of GIST originating from the small bowel and the stomach, which were preoperatively misdiagnosed as a uterine leiomyoma and an ovarian tumor, respectively. The ultrasonographic differential diagnosis of these pelvic masses is discussed.