Non-chromaffin, non-functioning retroperitoneal paragangliomas: a report of three additional cases with a review of the literature.

A review of the literature has revealed only 24 cases of retroperitoneal non-functional paraganglioma recorded up to the present date. This report presents three additional cases, in two of which metastasis had occurred at the time of surgery. The clinical presentation and the biological behaviour of these tumours are reviewed in detail, as also are recommendations regarding therapy.