Additional diagnostic value of cervical ultrasound in the detection of cervical lymph node metastases in patients with esophageal cancer

TL;DR

This study found that cervical ultrasound does not add value beyond PET-CT in detecting cervical lymph node metastases in esophageal cancer patients.

Contribution

The study provides evidence that cervical ultrasound is not necessary after a negative PET-CT scan in this patient group.

Findings

Cervical ultrasound had high sensitivity but low positive predictive value for detecting metastases.

PET-CT showed higher specificity and positive predictive value compared to ultrasound.

Using ultrasound increased unnecessary fine needle aspirations for benign lymph nodes.

Abstract

In Western Europe, esophageal cancer patients with cervical lymph node metastases are considered to have stage IV disease and are generally not eligible for curative treatment. While cervical ultrasound was part of standard diagnostic workup, its added value after negative 18FDG PET-CT is debated, and ultrasound is no longer in the Dutch guideline as standard workup modality. This study assessed the diagnostic accuracy of ultrasound for the detection of cervical lymph node metastases in esophageal cancer patients. This retrospective cohort study included all esophageal cancer patients referred to or diagnosed at the Amsterdam UMC between January 2014 and January 2021. Radiology and multidisciplinary team meeting reports were reviewed to identify patients with suspicious cervical lymph node(s). Primary outcome was the detection rate of cervical lymph node metastases on ultrasound and/or 18FDG PET-CT. The gold standard was fine needle aspiration. This study included 747 patients; median age was 67 years. Patients were predominantly male (75.5%) and majority had an adenocarcinoma (72.0%). Total of 112 (15.0%) patients had suspicious cervical lymph nodes, with malignancy confirmed in 38 cases. Cervical ultrasound showed high sensitivity (94.7%), but low positive predictive value (37.1%) compared to 18FDG PET-CT, which had 100% sensitivity, 91.3% specificity, and 71.7% PPV. This study demonstrated that cervical ultrasound offers no additional diagnostic value over 18FDG PET-CT alone in the assessment of cervical lymph node metastases during diagnostic workup for esophageal cancer and increases the number of fine needle aspirations conducted for benign cervical lymph nodes.

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