18‐Fluoro‐2‐deoxyglucose positron emission tomography in detecting residual/recurrent nasopharyngeal carcinomas and comparison with magnetic resonance imaging

BACKGROUND It is known that 18‐fluoro‐2‐deoxyglucose positron emission tomography (FDG‐PET) is effective in the early detection of residual/recurrent nasopharyngeal carcinomas (NPC). To compare FDG‐PET with the conventional magnetic resonance imaging (MRI) for the detection of residual/recurrent NPC, the authors studied 67 follow‐up cases of patients with NPC using both FDG‐PET and MRI. METHODS From February 1997 to February 2001, 67 NPC patients (14 women, 53 men; age range, 16–67 years; mean age, 46.6 ± 12.5 years) were recruited. Both FDG‐PET and MRI of the head and neck area for each patient were performed at least 4 months (duration range, 4–70 months; mean, 14 ± 13.5 months) after radiotherapy or radiotherapy with concurrent chemotherapy. The final diagnosis was confirmed by biopsy or clinical follow‐up for at least 6 months. RESULTS The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of FDG‐PET images were 100%, 93.4%, 95.5%, 87.5%, and 100%, respectively. In contrast, the sensitivity, specificity, accuracy, PPV, and NPV of the MRI scans were 61.9%, 43.5%, 49.3%, 33.3%, and 70.0%, respectively. CONCLUSIONS The results of the current study suggest that FDG‐PET is much more effective than MRI in detecting residual/recurrent NPC. Cancer 2003;98:283–7. © 2003 American Cancer Society. DOI 10.1002/cncr.11519 The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of 18‐fluoro‐2‐deoxyglucose positron emission tomography (FDG‐PET) images were 100%, 93.4%, 95.5%, 87.5%, and 100%, respectively. The results of the current study suggest that FDG‐PET is much more effective in detecting residual/recurrent nasopharyngeal carctinomas than magnetic resonance imaging.