Interesting ImageF-18 FDG PET/CT Imaging in a Case of Primary Choriocarcinoma in the RetroperitoneumCimarelli, Sébastien, MD*; Deshayes, Emmanuel, MD*; Mognetti, Thomas, MD*; Biron, Pierre, MD†; Desuzinges, Claude, MD*; Rivoire, Michel, MD, PhD‡; Giammarile, Francesco, MD, PhD§Author Information From the *Service de Médecine Nucléaire, Centre Léon Bérard, Université de Lyon, Lyon, France; †Département de Médecine, Centre Léon Bérard, Université de Lyon, Lyon, France; ‡Département de Chirurgie, Centre Léon Bérard, Université de Lyon, Lyon, France; and §Service de Médecine Nucléaire, Hôpital Lyon-Sud, Hospices Civils de Lyon, Lyon, France. Received for publication November 5, 2008; accepted March 16, 2009. Reprints: Sébastien Cimarelli, MD, Service de Médecine Nucléaire, Centre Léon Bérard, 28, Rue Laënnec, 69373 Lyon Cedex 08, France. E-mail: email@example.com. Clinical Nuclear Medicine: July 2009 - Volume 34 - Issue 7 - p 449-451 doi: 10.1097/RLU.0b013e3181a7d0cd Buy Metrics Abstract Nonseminomatous germ cell tumors (GCTs) represent 60% of all GCTs, the most common malignancy in young men. Extragonadal primary GCTs are a rare entity and their origin remains unclear. F-18 fluorodeoxyglucose positron emission tomography (PET) is a promising imaging tool for GCT staging and treatment evaluation. We report the case of a 23-year-old man presenting with retroperitoneal primary choriocarcinoma associated with pulmonary and hepatic metastases. In addition to conventional imaging techniques, the F-18 fluorodeoxyglucose PET evaluation at staging and after chemotherapy improved the management of this patient. Particularly, PET findings before surgery were correlated with histologic results. © 2009 Lippincott Williams & Wilkins, Inc.