FDG PET Imaging of Head and Neck Cancers

In initial staging of head and neck cancers, the addition of FDG PET to conventional imaging improves the accuracy for cervical nodal metastases. The sensitivity of FDG PET is, however, limited in nodes <1 cm and in completely necrotic nodes. In the posttherapy setting, PET scans obtained at least 10 weeks after radiotherapy have an excellent predictive value to rule out residual disease. Due to the limited positive predictive value of FDG PET after radiation therapy, a positive PET scan needs to be confirmed before management decisions are made.