CT diagnosis of retroperitoneal malignant stromal tumors

Objective To investigate the CT features of retroperitoneal malignant stromal Tumors.Methods CT findings of 8 cases of retroperitoneal malignant stromal tumors were retrospectively analyzed.All patients were given CT plain scan and dual-phase enhancement scan.Results In all the cases the mass was isolated,with a mean diameter of 14.8 cm;diameter was above 10 cm in 75% cases(6/8).The plain CT showed the tumors were solid and cystic,which mainly consisted of an outer solid part and central necrosis or cysts of various degrees.The solid part of tumors showed nonhomogeneous enhancement in dual-phase enhancement CT scan.The enhancement degree on venous phase was higher than that on arterial phase.There was no enhancement of cystic degeneration and necrosis in tumors.Pathological results revealed that there were 6 cases of high-grade malignant tumors,1 case of low-grade malignant tumor and 1 case of latent malignant tumor.Conclusion Retroperitoneal malignant stromal tumors have some CT features which are informative to diagnosis and treatment.