Direct comparison of F-18-FDG PET and ultrasound in the follow-up of patients with squamous cell cancer of the head and neck

Aim: The objective of this study was to compare screening ultrasound (US) o btained in patients with squamous cell carcinoma of the head and neck with F-18-FDG PET and to evaluate if US obtained before F-18-FDG PET has the pot ential to enhance patient management by the detection of additional lesions . Method: 28 patients were prospectively included in the study (7 females a nd 21 males, range: 28-82 years). All had one follow-up examination after s urgical treatment and/or radio therapy using a combination of US and F-18-F DG PET on the same day (6-35 months alter the end of treatment). Outcome wa s determined by either biopsy-proven cancer recurrence or negative clinical follow-up for additional 6 months after this examination. Results: Regardi ng only the regions of the neck evaluated with both methods, US detected 25 suspect lesions vs. 9 lesions detected by F-18-FDG PET. Descriptive statis tical analysis showed better sensitivity, specificity and accuracy of F-18- FDG PET. Only in 3 patients a lesion was detected in the some anatomical re gion using both methods. One patient was false positive with both methods. In another patient US detected a calcified right carotid artery plaque that lead to surgical therapy. Conclusion: F-18-FDG PET is better for the detec tion of clinically relevant lesions in the follow-up of patients with squam ous cell carcinoma of the head and neck. In this study, the additional valu e of morphological information obtained by screening US performed before th e PET scan is limited. US may not be a suitable test to improve interpretat ion of PET examinations.