2017 Volume 42 Issue 1 Pages 115-121
A 84-year-old man was reffered to our hospital because of a growing mass in his left inguinal area. Abdominal enhanced CT showed a large tumor, 19cm in a diameter which occupied left lower abdomen and grow into the inguinal canal. FDG-PET CT revealed a FDG accumulation in the tumor. The tumor showed a low signal intensity on a T1-weighted image, a high signal intensity on a T2-weighted image and a heterogenous contrast effect on contrast-enhanced MRI. Although it was suspected malignant stromal tumor or sarcoma, we did not do biopsy of the tumor because the risk of dissemination. For the purpose of diagnosis and total removal of the tumor, operation was underwent. Histopathological examination revealed growth of spindle cells, and immunohistopathological staining was positive for CDK4, MDM2 and p16, finally it was diagnosed retroperitoneal dedifferentiated liposarcoma. Whereas, the MIB-I positive rate was 30%. The patient is doing well one year and half after surgery, with no signs of reccurrence.
