[Comparative study on computed tomography features of gastrointestinal schwannomas and gastrointestinal stromal tumors].

OBJECTIVE: To compare the CT image of gastrointestinal schwannomas (GIS) and gastrointestinal stromal tumors(GIST), and to find the CT features to be helpful for differentiation of GIS from GIST.

METHODS: Clinical and iconography data of 15 GIS patients and 50 GIST patients who underwent stomach CT scan with postoperatively confirmed histopathology between January 2000 and July 2014 in our department were collected retrospectively. CT findings of these two tumors were compared. Then the ROC curve was drawn based on the significant CT findings and area under the curve (AUC) was calculated to assess the sensibility and specificity for the differential diagnosis of GIS and GIST.

RESULT: CT findings, such as the tumor size, shape, cystic change, perilesional lymph nodes, vessel seeding, enhancement pattern and degree, absolute and standardized CT value were significantly different between GIS and GIST(all P<0.05). Among the CT findings, tumor size, cystic change, perilesional lymph nodes, enhancement pattern and arterial phase standardized CT value (Sa) were better differential than others (all AUC>0.7). Tumor size showed the highest sensibility(90%), and cystic change and Sa showed the highest specificity(87%).

CONCLUSIONS: GIS seems to show a homogeneous tumor more frequently, presenting light and moderate enhancement pattern and obvious enhancement of perilesional lymph nodes, while GIST seems to reveal malignant features, such as abundant blood supply, larger volume, frequent necrosis and cystic change. Cystic change and Sa value possess the better differential ability in diagnosis of these two tumors.