CT and MRI Features of Intra-abdominal Desmoplastic Small Round Cell Tumors

Objective To investigate the CT and MRI features of intra-abdominal desmoplastic small round cell tumors(DSRCT).Materials and Methods Clinical and image data of 7 cases with DSRCT verified by pathology or stereotactic biopsy were analyzed retrospectively.Results There were single lesions in 2 cases and multiple nodular tumors in 5 cases.The tumor diameter was large than 10 cm in 5 cases.CT showed a large,lobulated or nodular,heterogeneous,low-attenuation mass in the abdominopelvic district with several lamellar necrotic zone in the tumors.5 cases appeared stippled calcification in the tumors.Contrast-enhanced CT scan revealed mild or medium heterogeneous enhancement in 2 or 5 cases.Peritoneal involvement was most commonly seen The mass trended to lapse,encase and offend surrounding tissues and vessels without any obvious organ origin.5 cases showed enhanced septative vessels in abdominopelvic tumors.2 cases were associated with ascites.The liver and bone metastases were found in 2 cases and lymphonode metastases in 3 cases.MRI showed iso-hypotensity signal in T1WI and slightly hypertensity signal in T2WI.Cystic and necrotic zone appeared obvious hypertensity signal in T2WI.Conclusion Intra-abdominal DSRCT has some CT and MRI features.