Introduction: Where chemoradiotherapy or radiotherapy alone with curative intent is used as the primary treatment of locally advanced head and neck cancers, salvage surgery may offer a second chance of cure in the face of recurrent or residual disease. Early detection of recurrent or residual disease is therefore the key to facilitating timely and efficacious salvage surgery. CT and MRI can be difficult to interpret in the posttreatment neck. Functional imaging, such as 18F-FDG PET/CT, has the potential to improve restaging accuracy. The aim of our study was to assess the efficacy of 18F-FDG PET/CT performed 3 months following primary treatment of head and neck cancer.
Methods: We retrospectively reviewed 35 patients with head and neck squamous cell cancer (mean age, 61 years; 28 male patients) who underwent 18F-FDG PET/CT imaging at 3 months following primary treatment, which included chemoradiotherapy (n = 31) or radiotherapy alone (n = 4). Patient follow-up was available for at least 12 months (range, 12–48 months; median, 36 months). Scans were categorized as true positive, true negative, false positive, and false negative based on clinicoradiological follow-up and histology.
Results: Twenty patients had negative scans with no recurrence during the follow-up period, and 3 had false-negative scans with recurrent disease at 5, 8, and 12 months. Eleven patients had true-positive scans, confirmed histologically in all, and there was 1 false-positive scan giving a sensitivity of 79%, specificity of 96%, positive predictive value of 92%, negative predictive value of 87%, and overall accuracy of 89%.
Conclusions: 18F-FDG PET/CT is an accurate method for assessing response after primary locally advanced head and neck cancer treatment. Although false-positive scans are rare, a few patients will have a relapse after a negative scan, and so continued close follow-up is required.
From the Departments of *Nuclear Medicine and †Head and Neck Oncology, Guys and St Thomas’ NHS Foundation Trust; and ‡Division of Imaging Sciences and Biomedical Engineering, Kings College London, London, United Kingdom.
Received for publication August 31, 2012; revision accepted November 18, 2012.
Conflicts of interest and sources of funding: This study was supported by the NIHR Biomedical Research Centre of Guys & St Thomas’ NHS Trust in partnership, Kings College London and and UCL Comprehensive Cancer Imaging Centre, funded by the CRUK and EPSRC in association with the MRC and DoH (England).
Reprints: Gary J.R. Cook, MD, FRCR, Clinical PET Centre, Division of Imaging Sciences and Biomedical Engineering, Kings College London, St Thomas’ Hospital, London, SE1 7EH United Kingdom. E-mail: firstname.lastname@example.org.