Objective:The purpose of this study was to search the ultrasound features of small intestinal stromal tumor(SIST) in women by reviewing their clinical data.Methods:The study group consisted of 18 female patients with pathologically proven SIST in our hospital from 2000 to 2009.Medical records were reviewed for clinical information such as manifestation,findings of ultrasonography and immunohistochemical phenotype.Results:The average age of 18 female patients with SIST was 55.2 years(ranged,39-84 years).Seventeen cases of them had abnormal hypogastric masses,no mass in one case.The shapes of masses were round or lobulate beside tightly uterus or ovary.The echo of masses was low.It’s borders were clear and sometimes irregular.The sizes of the masses varied from 6.89-193.05 cm3,the diameter ranged from 24 mm-110 mm,85.3% of which 50 mm-110 mm.There were rare color flow signals under color Doppler velocity mode or color Doppler power mode.Exploratory laparotomy confirmed that 16 cases of the tumors originated from small intestine,and 2 cases from the ileocecal.The positive rate of the immunohistochemical phenotype of CD117 was 88.2%,and CD34 was 76.5%.The examination of pathology confirmed that 16 cases were malignant and 2 cases borderline tumors.Eighteen cases underwent radical surgical resection.Conclusion:The characteristics of SISTs in women pelvic cavity are:age > 40 years,a mass(proven not from productive system by ultrasonography) in pelvic cavity,melena,positive findings in pathology and CD117/CD34,especially notice masses which diameter is more than 50 mm and possess potential malignant.Ultrasonography is a convenient and effective tool of screening SISTs. Objective: The purpose of this study was to search the ultrasound features of small intestinal stromal tumor (SIST) in women by reviewing their clinical data. Methods: The study group consisted of 18 female patients with pathologically proven SIST in our hospital from 2000 to 2009 Results: The average age of 18 female patients with SIST was 55.2 years (ranged, 39-84 years). Seventeen cases of them had abnormal hypogastric masses , no mass in one case. The shapes of masses were round or lobulate beside tightly uterus or ovary. The echo of masses was low. It’s borders were clear and sometimes irregular. These sizes of the masses varied from 6.89-193.05 cm3, the diameter ranged from 24 mm to 110 mm, 85.3% of which 50 mm to 110 mm. There were few color flow signals under color Doppler velocity mode or color Doppler power mode. Experimental laparotomy confirmed that 16 cases of t The tumors originated from small intestine, and 2 cases from the ileocecal. The positive rate of the immunohistochemical phenotype of CD117 was 88.2%, and CD34 was 76.5%. The examination of pathology confirmed that 16 cases were malignant and 2 cases borderline tumors. Eighteen Cases underwent radical surgical resection. Conlusion: The characteristics of SISTs in women pelvic cavity are: age> 40 years, a mass (proven not from productive system by ultrasonography) in pelvic cavity, melena, positive findings in pathology and CD117 / CD34, especially notice masses which diameter is more than 50 mm and possess potential malignant. Ultrasonography is a convenient and effective tool of screening SISTs.