Hybrid positron emission tomography imaging for initial staging of sinonasal tumors: Total lesion glycolysis as prognosticator of treatment response

Abstract

Background: To assess hybrid positron emission tomography (PET) imaging in the initial staging and outcome prediction of sinonasal malignancies. Methods: Retrospective study on patients with sinonasal malignancies undergoing hybrid PET imaging for initial staging. Results: Complete remission (CR) was achieved in 45 of 65 patients (69.2%). Overall sensitivity for detection of primaries using 18F-fluoro-deoxy-D-glucose PET (FDG-PET) was 95.4%, for lymph node metastases 100% and distant metastases (DM) 100%. On univariate analysis, PET parameter total lesion glycolysis (TLG) was associated with achieving CR after primary treatment (176.8 ± 157.2 vs 83.7 ± 110.8, P = .03). Multivariate logistic regression demonstrated that TLG adjusted for the T classification best predicted achievement of CR. Conclusions: Hybrid PET imaging yields an excellent sensitivity in detecting primary tumors, lymph node metastases and DM in sinonasal malignancies. TLG of the primary tumor is an independent prognostic factor for achieving CR after initial treatment.

Whole‐body hybrid positron emission tomography imaging yields clinically relevant information in the staging and restaging of sinonasal tumors

“…However, a more thorough assessment of the primary tumor in PET imaging is complicated by the fact that different histopathological subtypes of sinonasal tumors may reveal different FDG‐avidity and by the “spillover” of activity from normal brain tissue. Typically, sinonasal undifferentiated carcinoma (SNUC) and olfactory neuroblastoma tend to exhibit higher FDG uptake, compared to adenoidcystic carcinoma and sinonasal adenocarcinoma 10,11,31,32 . Furthermore, locally confined, and superficial tumors are a common challenge, since they may appear FDG‐negative 10,33 .…”

“…FDG uptake by inflammatory LN is a frequent source of false‐positives, reverting into comparably low positive predictive value and specificity of FDG‐PET 10,11 . The additional value of PET in detecting LN metastasis is demonstrated by Figure 5.…”

“…To address this shortcoming of conventional imaging modalities, the use of hybrid PET imaging may generate added radiological value. Recent data, addressing the primary staging of sinonasal tumors, demonstrated that hybrid PET imaging yields an excellent sensitivity (95%–100%) for detecting the primary tumor 10,12,30 . However, a more thorough assessment of the primary tumor in PET imaging is complicated by the fact that different histopathological subtypes of sinonasal tumors may reveal different FDG‐avidity and by the “spillover” of activity from normal brain tissue.…”

“…FDG uptake by inflammatory LN is a frequent source of false-positives, reverting into comparably low positive predictive value and specificity of FDG-PET. 10,11 The additional value of PET in detecting LN metastasis is demonstrated by Figure 5. Since we did not classify FNA of FDG-avid LN as clinically relevant information, the vast majority of ARI retrieved from hybrid PET imaging did not have clinically relevant information (Figure 3).…”

“…Magnetic resonance imaging helps to delineate tumor from surrounding tissue such as dura and periorbita and is capable to identify perineural spread, bone marrow infiltration, and local metastases 8,9 . In the last decades, 2‐[ 18 F]‐fluorodeoxy‐ d ‐glucose (FDG) positron emission tomography (PET)/CT (FDG‐PET/CT) and more recently FDG‐PET/MRI emerged as potential alternatives for the assessment of sinonasal tumors, providing information on both metabolic activity and local extent of the primary tumor and on the presence of regional and distant metastases (DM) 10,11 . While various studies have investigated the diagnostic accuracy of hybrid PET imaging for squamous cell carcinoma (SCC) of the upper aero‐digestive tract, only a few studies addressed its use for primary sinonasal malignancies 10,12–16 .…”