[Imaging of non-functional retroperitoneal paragangliomas. Apropos of a case].

The non functional extraperitoneal paragangliomas are rare tumors (less than 50 cases reported). We report a case with ultrasound and CT scan imaging. The tumor is usually large with important necrotic areas leading to a cystic aspect. The malignant tumors more frequent than the benign tumors present with a regional extension and delayed metastasis.