USEFULNESS OF 201TI SPECT/CT RELATIVE TO 18F-FDG PET/CT IN DETECTING RECURRENT SKULL BASE NASOPHARYNGEAL CARCINOMA

Background. This study was designed to compare (TI)-T-201 single photon emission computed tomography (SPECT)/CT with 18-fluoro-2-deoxyglucose (F-18-FDG) PET/CT in diagnosing recurrent skull base nasopharyngeal carcinoma (NPC). Methods. Twenty-seven patients were recruited. Both (TI)-T-201 SPECT/CT and F-18-FDG PET/CT for each patient were performed at least 4 months later after initial therapy. Results. The sensitivity and specificity for (TI)-T-201 SPECT/CT were 66.7% and 100%, and those for F-18-FDG PET/CT were 86.7% and 75.0%. Lesion/background ratios were obtained for the 10 lesions that were both SPECT and PET true positive. For the 8 patients with recurrences in nasopharyngeal regions, PET lesion/background ratios were all higher than SPECT lesion/background ratios. For the 2 patients with intracranial metastases, SPECT lesion/background ratios were higher than PET lesion/background ratios. Conclusion. (TI)-T-201 SPECT/CT is as effective as F-18-FDG PET/CT in detecting recurrent NPC. For intracranal recurrence, (TI)-T-201 SPECT, because of its high intracranial lesion/background ratio, is probably better than F-18-FDG PET. (c) 2009 Wiley Periodicals, Inc. Head Neck 31: 717-724, 2009