Placental-site trophoblastic tumor and fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography.

Objective: Pre-operative imaging characteristics of placental site trophoblastic tumor (PSTT) are variable and non-specific. Although magnetic resonance imaging (MRI), ultrasonography, chest CT and X-rays findings have been studied the fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) findings of PSTT have not been previously documented. We present the findings of a first case of PSTT evaluated by pre-operative ¹⁸F-FDG PET/CT. A suspicious mass was biopsied and revealed PSTT in post-operative pathological examination. She was referred to the gynecology-oncology department. The ¹⁸F-FDG PET/CT scan revealed a 27 x 20 mm laterally expanded lesion that showed increased ¹⁸F-FDG uptake (SUVmax: 5.20) on the right isthmus of the uterus. The ¹⁸F-FDG PET/CT findings were in accordance with those from chest X-ray/s, CT and pelvic ultrasonography. A systematic, nerve sparing, paraaortic and pelvic lymph node dissection along with total hysterectomy and salpingoopherectomy was performed. The patient was discharged uneventfully.

Conclusions: ¹⁸F-FDG PET/CT scan was able to identify the mass in the uterus which was shown by pathology to be PSTT. This finding of PET/CT was in accordance with other imaging techniques. Lymphatic mapping of ¹⁸F-FDG PET/CT in this case was also in accordance with surgery and pathology findings.