PET Oncology: Lymphoma
Krista Chambers, CNMT
Nuclear Medicine Technologist Student
Medical College of Georgia
Patient History:
The patient is a 42 year old female diagnosed with lymphoma. This exam was compared to the recent Computed Tomography scan of the neck and chest on December 22, 2004. The CT scan showed an increase in the number and size of lymph nodes in the neck that were more prominent than at the time of previous PET scan. The left supraclavicular region shows increase that extends to the thoracic inlet level into the upper mediastinum.
Brief History:
The patient was instructed to fast with the exception of water from midnight the night before to the time of exam. This is required for all PET scans to minimize competitive inhibition FDG uptake and to decrease the heart uptake. When the patient arrived to the PET center, the procedure was explained to the patient along with verification of identity. An IV was started and made sure correct placement in the vein with a saline flush. The patient’s blood glucose level was checked to insure proper glucose levels. Glucose level between 90-150mg/dl is adequate for F18 FDG uptake and scanning. Levels too high will decrease uptake of the FDG in tumors. Once glucose level was approved, 15mCi fluorine FDG-18 was injected followed by a 250mL drip bag of saline. The patient relaxed in the room for 45 minutes post injection to ensure no muscle uptake. This is standard with all PET scans.
Radiopharmacy:
15mCi fluorine FDG-18 injected then assayed in the dose calibrator for residual activity. Time of injection and then residual should be written down. The residual activity is important in the calculation of the standard uptake value.