Positron emission tomography–CT prediction of occult nodal metastasis in recurrent laryngeal cancer

Background: The purpose of this study was to evaluate the predictive value of positron emission tomography (PET)-CT in identifying occult nodal metastasis in clinically and radiographically N0 patients with recurrent laryngeal cancer undergoing salvage laryngectomy. Methods: Retrospective review of 46 clinically and radiographically N0 patients with recurrent laryngeal cancer who underwent a PET-CT examination before salvage laryngectomy with neck dissection from January 1, 2002, to December 31, 2014, was performed. Results: Two patients (16.7%) had true-positive PET-CT results, whereas 10 patients (83.3%) had false-negative scans, 1 patient (2.9%) had a false-positive result and 33 patients (97.1%) had a true-negative PET-CT. The sensitivity of PET-CT was 16.7% (95% confidence interval [CI], 3.5% to 46.0%) with a specificity of 97.1% (95% CI, 83.8% to 99.9%), positive predictive value (PPV) of 66.7% (95% CI, 20.2% to 94.4%), and negative predictive value (NPV) of 76.7% (95% CI, 62.1% to 87.0%). Conclusion: PET-CT has poor sensitivity and NPV making PET-CT an imperfect predictor of nodal disease in recurrent laryngeal cancer.