Follow-up FDG PET in the Evaluation of Unexplained Focal Activity in the Abdomen

Multiple organ metastases from ameloblastoma detected by FDG PET/CT imaging

A 74-year-old patient was admitted to our hospital with recurrent ameloblastoma of the right mandible. Multiple lung nodules were noted during the presurgical evaluation. FDG PET/CT was subsequently performed to assess the nature of the nodules and search the possible primary tumors. The images showed abnormal FDG activity not only in the lung nodules but also in the lumbar vertebral body and the liver. Pathologic examination after hepatic biopsy demonstrated metastases from ameloblastoma.

Earlier detection of bone metastases from pleomorphic liposarcoma in a pediatric patient by FDG PET/CT than planar 99mTc MDP bone scan

Bone scintigraphy using (99m)TC MDP (technetium-99m methylene diphosphonate) is a routine procedure for evaluation of osteoblastic metastases; however, its sensitivity compared with FDG PET/CT in a variety of malignancies remains to be established. We report a case of multiple osseous metastases revealed by FDG PET/CT in an 8-year-old girl with pleomorphic liposarcoma. Many of these osseous lesions were not visualized on the MDP planar bone scintigraphy performed 24 hours after PET/CT scan, becoming evident only on repeat bone scan performed 3 months later. The case suggests that FDG PET/CT has higher sensitivity in detecting osteoblastic metastases in pleomorphic liposarcoma.