Comparison between anatomical cross-sectional imaging and 18F-FDG PET/CT in the staging, restaging, treatment response, and long-term surveillance of squamous cell head and neck cancer: a systematic literature overview.

The outcome of head and neck squamous cell cancer depends primarily on its prompt diagnosis and treatment. Unfortunately, in many cases ominous prognostic factors such as lymph node metastases or osteomandibular extension are present at the time of diagnosis. We review the relative efficacy of contrast-enhanced computed tomography (ceCT), MRI, and F-fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) in the early detection of head and neck squamous cell cancer, as well as its impact on treatment management and outcomes. Medline and Web of Knowledge databases, from 2000 to January 2013, were evaluated. Ninety-seven reports were selected, but only 11 studies comparing PET or PET/CT with CT and 11 comparing PET or PET/CT with MRI were found appropriate for analysis. ceCT and MRI continue to be the reference imaging modalities for the study of primary tumors, especially in the evaluation of the extension of disease and its relationship with nearby anatomical structures. There is increasing evidence that F-FDG PET/ceCT can provide accurate anatomical details similar to ceCT alone, as well as accurate information on osteomandibular tumor invasion similar to MRI. The major advantage of PET/CT over other imaging methods is its ability to detect relatively small lymph node metastases located in difficult-to-interpret positions. PET/CT is also highly sensitive for the detection of distant metastases and in assessing the response to chemotherapy or chemoradiation treatment and in predicting outcome. ceCT and MRI are the gold standards for evaluating primary and osteomandibular tumoral infiltration. F-FDG PET/CT plays a major role in the detection of lymph node and distant metastases, in assessing the response to neoadjuvant/adjuvant chemotherapy or chemoradiation therapy, and in predicting outcome.