OBJECTIVETo investigate the clinical diagnosis, treatment and immunohistochemical characteristics of rectal stromal tumors.

METHODSImmunohistochemical expression of CD117 was retrieved in 20 cases of mesenchymal tumors of the rectum. And we analyzed the immunohistochemical characteristics, clinical data of rectal stromal tumors, and the results retrospectively.

RESULTSSixteen cases of rectal stromal tumors, 3 cases of leiomyosarcomas and 1 case of schwannoma were diagnosed. Histologically, 2 cases of GISTs were classified as benign, 1 as borderline and 13 as malignant. All of rectal stromal tumors (100%) were strongly positive for CD117, and 14 cases (88%) positive for CD34. The demographic profile of rectal stromal tumors showed a male predominance with average age of 60 years old. The main symptoms were urinary retention, constipation and abdominal pain. 14 cases were positive in digital rectal examination. The recurrence rate of local and radical resection in malignant stromal tumors was 4/4 and 3/6. 1, 3, 5-year survival rates were 89%, 64%, 48%, respectively. After operation mean survival time of was 47 months.

CONCLUSIONSThe specific GIST constituted the majority of mesenchymal tumors in rectum. It usually showed malignant biological behavior. Invasion and recurrence were common. Earlier diagnosis and radical resection had better prognosis. Periodically following up can help to detect the recurrence timely.