Role of Whole-Body 18 F-FDG PET/CT in Screening for Metastases in Newly Diagnosed Sinonasal Malignancies.

OBJECTIVE: The aim of this study is to assess the utility of pretreatment whole-body 18 F-FDG PET/CT in screening for distant metastasis (DM) and regional lymphatic metastasis (LM).

MATERIALS AND METHODS: Eighty-nine consecutive patients with untreated sinonasal malignant lesions (32 women and 57 men; mean age, 62 years) underwent whole-body FDG PET/CT between January 2009 and August 2017. A retrospective analysis was performed to determine the presence of DM and LM. Any suspected metastases were confirmed by histopathologic analysis or clinical and imaging follow-up in the subsequent 12 months. The statistics were verified by comparing FDG PET/CT results with a reference standard.

RESULTS: Overall, the frequency of DM was 24% (21/89), of which 81% (17/21) were identified by whole-body FDG PET/CT. The sensitivity and specificity of FDG PET/CT in predicting DM were 81% (95% CI, 62-95%) and 99% (95% CI, 82-100%), respectively. The most common DM sites were the lungs (n = 6; 28%) and bones (n = 5; 24%), followed by the liver (n = 2; 10%), brain (n = 1; 5%), and spinal canal (n = 1; 5%), with six patients (28%) having DMs at multiple sites. Overall, the frequency of LM according to the reference standard was 20%, of which 83% (15/18) were confirmed with FDG PET/CT. The sensitivity and specificity of FDG PET/CT in detecting LM were 83% (95% CI, 68-97%) and 96% (95% CI, 77-100%), respectively.

CONCLUSION: Our study showed that whole-body FDG PET/CT can be used as a screening tool for the detection of DM and LM in sinonasal neoplasms and could be performed as part of the routine pretreatment evaluation of metastatic workup.