Metastasis detection with 18 FDG-positron emission tomography/computed tomography in gestational trophoblastic...

The imaging methods proposed by the International Consensus for the Diagnosis of Metastases in Trophoblastic Neoplasia are sufficient to stage the disease in most cases. However, there are 2 circumstances in which a more accurate imaging method is necessary: condemonstrate tl fusing images in conventional studies and persistent low 18 FDG-PET/CT human chorionic gonadotropin (hCG) values. Eighteen-fluoro-2-deoxyglucose-positron emission tomography/ computed tomography (18 FDG-PET/CT) can be helpful in these cases.

Case 1. A 51-year-old woman was referred to the Hospital Universitario de Caracas from another hospital with a diagnosis of cervical adenosquamous carcinoma. She complained of vaginal bleeding; clinical and sonographic evaluation demonstrated a tumor in the uterus and lower third of the vagina. A new histopathologic study was performed, and choriocarcinoma (CC) was diagnosed and staged as International Federation of Gynecologists and Obstetricians (FIGO) II:12 The im aging studies were confusing, so an 18 FDG-PET/CT was performed, showing multiple nodules in the lungs. Case 2. A 25-year-old woman was admitted with symptoms that mimicked those of ectopic pregnancy; a left salpingectomy was performed, with a histopathologic report of CC. It was classified as FIGO stage 11:4. Treatment consisted of chemotherapy, hysterectomy and 1 pelvic tumor resection. Two years after discontinuing therapy, persistent low hCG values were detected without evident metastatic disease demonstrated by CT. Eighteen FDG-PET/CT showed multiple pulmonary nodules.

Eighteen FDG-PET/CT seems to reveal metastases that are either confusing or not detected by other imaging techniques currently accepted in most gestational trophoblastic neoplasia protocols.