Desmoplastic small round cell tumor (DSRCT) is a member of the family of small round blue cell tumors. It is common in adolescent male patients. Patients usually present with abdominal pain or swelling. It is a rare and very aggressive mesenchymal neoplasm that grows along the peritoneal surfaces.

Imaging features include solitary or multiple soft tissue masses arising from the peritoneum, omentum, or mesentery without a definite organ of origin.

Appearances carry a differential diagnosis, as it cannot be differentiated from other malignant peritoneal tumors such as mesothelioma, rhabdomyosarcoma, lymphoma, desmoid, or neuroblastoma on imaging alone.