Long-term follow-up using 18F-FDG PET/CT for postoperative olfactory neuroblastoma

The present study evaluated the usefulness of postoperative fluorine-18 fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) in the management of olfactory neuroblastoma (ONB).

Ten patients (eight men and two women; mean age, 48.5 years) with histologically confirmed ONB who underwent craniofacial resection were retrospectively included in this study. A total of 42 whole-body F-FDG PET/CT scans for postoperative surveillance or restaging were reviewed. The mean time from operation until the PET/CT scan was 42.1 months. We evaluated the F-FDG uptake and the presence of recurrent lesions during the follow-up period and compared the PET/CT results with the results of MRI and clinical examination (endoscopy).

Seven of the 10 patients had 24 recurrent lesions, and 18 of these recurrent lesions (seven local recurrences, eight cervical lymph node metastases, one intracranial metastasis, and two distant metastases) were F-FDG positive (75.0%). Three local recurrences and three intracranial metastases were false negative and were detected by endoscopy and MRI, respectively. The mean time from operation until recurrence was 51.4 months, and 17 lesions (70.8%) occurred more than 2 years after the initial operation.

Although F-FDG PET/CT is useful for the detection of postoperative recurrences of ONB, long-term follow-up combined with endoscopy and MRI is mandatory.