Presentation
Progressive weight loss and abdominal distension.
Patient Data



Large ill-defined heterogeneous soft tissue mass is seen centered on the left posterior pararenal space. It infiltrates the transversalis fascia, muscles of the posterior abdominal wall, infiltrates the left psoas muscle and medial aspect of the left kidney, and displaces the left kidney forward and upward. The mass shows minimal enhancement with extensive central necrosis. Hepatosplenomegaly, adrenal gland enlargement, and para-aortic lymph nodes are other findings.
Case Discussion
Retroperitoneal neoplasms are usually large at the time of presentation due to delay in their diagnosis. Differential diagnosis for retroperitoneal mass includes retroperitoneal sarcoma either liposarcoma, leiomyosarcoma, rhabdomyosarcoma and MFH, retroperitoneal metastasis and retroperitoneal lymphoma. This lesion was biopsied and revealed Non-Hodgkin lymphoma.