Clinical interest of F.D.G.-PET in head and neck cancers

FDT-PET imaging has become a major tool in the management of cancer patients including head and neck tumors. It is extremely useful for detecting unknown primary tumors or for detecting an additional primary tumor. It can help guiding biopsies of equivocal lesions located in regions that cannot easily be reached. The impact of PET is more limited for evaluating a known primary tumor. Its role for initial lymph node staging remains unclear, as its rather limited spatial resolution prevents the detection of the smallest nodal metastases, thus limiting the clinical impact. It could be help by picking up contralateral nodal lesions but prospective studies should clarify its real impact in clinically N0 patients. Up to now, the major indication for PET is the detection and staging of recurrences in patients previously treated by surgery and/or irradiation. Its potential for assessing the response to treatment early on after chemotherapy or later on after radiation therapy, as well as its prognostic value, may help the clinician to choose the best therapeutic regimen, in particular in high-risk patients. (author)