18F-FDG PET-CT as a supplement to CT/MRI for detection of nodal metastasis in hypopharyngeal SCC with palpably negative neck.

Abstract

To determine the diagnostic value of (18) F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) compared with CT or magnetic resonance (MR) imaging for the detection of nodal metastasis in patients with hypopharyngeal squamous cell carcinoma (SCC) with palpably negative neck and to assess the role of PET-CT as a supplement to CT/MR. Retrospective analysis. A total of 39 patients with palpably negative neck (36 men and 3 women; average age 65.4 years) underwent tumor resection and neck dissection as primary treatment. All patients were preoperatively evaluated with PET-CT and CT and/or MR, and imaging data were retrospectively reviewed. The diagnostic performance of PET-CT, CT/MR, and a combination of PET-CT and CT/MR was assessed using histopathologic results as a gold standard. Twenty (51.3%) of the 39 patients were found to have neck metastases. On a level-based analysis, the sensitivity of PET-CT, CT/MR, and combined interpretation of PET-CT and CT/MR was 65.7%, 57.1%, and 65.7%, respectively, but without statistical significance. Of the six patients who showed false negative neck findings based on CT/MR in addition to palpation, four cases were still missed with additional PET-CT. The addition of PET-CT examination to anatomic imaging involving CT and MR did not provide additional benefit for the preoperative evaluation of cervical nodal metastasis in patients with hypopharyngeal SCC with nonpalpable neck, yielding insufficient data to spare elective neck dissection.