Accuracy of computed tomography in determining the presence or absence of metastatic retropharyngeal adenopathy

Objective: To decide the accuracy of computed tomography in determining the presence or absence of metastatic retropharygeal adenopathy in patients with squamous cell carcinoma of the head and neck. Design: A comparison of the results of retrospective blinded review of preoperative computed tomographic scans with the histologic findings of retropharyngeal node dissection at the time of surgery. Setting: Academic tertiary care center. Patients: Twenty-six patients with advanced stage squamous cell carcinoma of the head and neck. Main Outcome Measures: Computed tomographic findings and histologic results of retropharyngeal node dissection. Results: The retropharyngeal nodes were pathologically positive for metastasis in 6 (23%) of the 26 patients. The radiologist (J.M.T.) correctly read the scan in 3 of 6 patients with histologically proved metastasis, and in 14 of 20 patients with histologic features negative for metastasis. The sensitivity of the radiologist reading was 50%, and the specificity was 70%. The positive predictive value was 33%, and the negative predictive value was 82%. Conclusion: The presence of retropharyngeal node metastasis cannot be determined by computed tomographic imaging alone.