FDG‐PET‐CT/MRI in head and neck squamous cell carcinoma: Impact on pretherapeutic N classification, detection of distant metastases, and second primary tumors

Abstract

Background To assess the effect of 18‐fluorodeoxyglucose positron emission tomography (FDG‐PET) in the pretherapeutic staging of N classification, detection rate of distant metastases, and second primaries. Methods Retrospective study on patients with head and neck carcinoma. We compared pretherapeutic N classification by ultrasound, computed tomography (CT)/magnetic resonance imaging (MRI), and FDG‐PET‐CT/MRI. Results A change in the N classification due to FDG‐PET‐CT/MRI was observed in 116 patients (39.5%) compared to N classification by ultrasound and fine‐needle aspiration cytology. Patients with advanced nodal classification (>N2a) were more likely to be reclassified. Distant metastases were detected in 19 patients and a total of 36 second primaries were diagnosed by FDG‐PET‐CT/MRI. Detection of distant metastases was more likely in regional advanced disease (>N2a). Smokers (>10 py) had a significantly higher risk of second primary. Conclusion FDG‐PET‐CT/MRI leads to a significant change in pretherapeutic N classification. The cumulative incidence of distant metastases and second primaries was 18.7%.

Improved diagnostic accuracy of hybrid positron emission tomography (PET) with tumor-specific radiotracer for head and neck squamous cell carcinoma staging

“…Current standard imaging for advanced head and neck squamous cell carcinoma (HSNCC) usually includes 18-fluorodeoxyglucose positron emission tomography (18F-FDG-PET), combined with either CT or MRI, which has gained wide application since its first description in clinical oncology by Beyer et al in 2000 (2). Adding hybrid 18F-FDG-PET to the diagnostic and staging process for HNSCC patients results in improved nodal classification and increased detection of distant metastases (3,4). Further, for patients with carcinoma of unknown primary (CUP) of the head and neck, hybrid 18F-FDG-PET is a precious tool for identifying and localizing the primary tumor (5).…”