Does [18F] fluorodeoxyglucose-positron emission tomography/computed tomography have a role in cervical nodal staging for esophageal squamous cell carcinoma?

Abstract

Accurate nodal staging is crucial for esophageal cancer. A prospective study was performed to assess the value of [18F] fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) for diagnosing cervical lymph node metastasis (LNM) of esophageal squamous cell carcinoma. From June 2018 to November 2018, 110 patients with resectable esophageal cancer were prospectively enrolled. Esophagectomy with 3-field lymphadenectomy was performed after FDG-PET/CT scanning. The primary end point was cervical LNM determined via postoperative histologic examination. The sensitivity (SE), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and accuracy (AC) of FDG-PET/CT for the assessment of LNM were determined using histologic results as reference standards. Positive lymph nodes as determined via FDG-PET/CT were detected in 61 patients (55.5%), of whom 13 (11.8%) had positive cervical lymph nodes. After surgery, 59 patients (53.6%) exhibited pathologic LNM, of whom 20 (18.2%) had cervical LNM. SE, SP, PPV, NPV, and AC were 65.6%, 61.2%, 67.8%, 58.8%, and 63.6%, respectively, with regards to diagnosing overall LNM, and were 45.0%, 95.6%, 69.2%, 88.7%, and 86.4%, respectively, for diagnosing cervical LNM. Of the 110 patients, 90 underwent both FDG-PET/CT scanning and ultrasonography in the neck, and there were no significant differences in SE, SP, PPV, NPV, or AC with respect to cervical LNM diagnosis between FDG-PET/CT and ultrasonography. For cervical LNM of esophageal squamous cell carcinoma, FDG-PET/CT scanning exhibited high specificity but low sensitivity, suggesting that it is of limited value for this purpose.