Retroperitoneal masses are extremely rare. They may be primary malignant, benign or metastatic. The majority of them are malignant. Possible causes that may reveal the etiology of these masses have not been clarified yet. However some predisposing factors have been identified. These masses are classified according to their histological types. Clinical signs are presence of abdominal mass and abdominal pain. A multidisciplinary approach for diagnosis and treatment in high-volume referral centers is ideal. Retroperitoneal masses are treated surgically as much as possible. It is important to achieve negative surgical margins. Optimal treatment approaches have not been standardized as of today. Anthracycline chemotherapy which may be combined with radiotherapy forms the basis of therapy. Developments related to targeted therapies are particularly promising.

Keywords: Retroperitoneal neoplasms, retroperitoneal liposarcoma, diagnosis, therapy