Cervical ultrasonography has no additional value over negative ¹⁸F-FDG PET/CT scans for diagnosing cervical lymph node metastases in patients with oesophageal cancer

Objectives: To investigate the additional value of cervical ultrasonography over ¹⁸F-FDG PET/CT for diagnosing cervical lymph node metastases in patients with newly diagnosed oesophageal cancer. Methods: Between January 2013 and January 2016, 163 patients with newly diagnosed oesophageal cancer underwent both cervical ultrasonography and ¹⁸F-FDG PET/CT at a tertiary referral centre in the Netherlands. Retrospective clinical data analysis was performed to assess the diagnostic value of cervical ultrasonography and ¹⁸F-FDG PET/CT for the detection of cervical lymph node metastases. Fine needle aspiration or clinical follow-up was used as reference standard. Results: The overall incidence of patients with cervical lymph node metastases was 14%. The sensitivity of ¹⁸F-FDG PET/CT to detect cervical lymph node metastases was 82% (95% CI 59–94%) and specificity was 91% (95% CI 85–95%). The sensitivity and specificity of cervical ultrasonography were 73% (95% CI 50–88%) and 84% (95% CI 77–90%), respectively. In patients with a negative ¹⁸F-FDG PET/CT, 12 of 133 (9%) patients had suspicious nodes on cervical ultrasonography. In all these 12 patients the nodes were confirmed benign. Conclusions: Cervical ultrasonography has no additional diagnostic value to a negative integrated ¹⁸F-FDG PET/CT for the detection of cervical lymph node metastases in patients with newly diagnosed oesophageal cancer. Key Points: • Cervical ultrasonography has no value over PET/CT in evaluating cervical node metastases.• PET/CT provides greater diagnostic confidence compared to cervical ultrasonography.• Cervical ultrasonography during standard diagnostic work-up may be considered unnecessary.• Cervical lesions on PET/CT require cytopathological confirmation by FNA.