[The accuracy of evaluating the response of metastatic lymph nodes after concurrent chemoradiotherapy in patients with head and neck squamous cell carcinoma].

Background: Concurrent chemoradiotherapy (CCRT) is used to treat advanced head and neck cancer. The accuracy of evaluating lymph nodes metastases following CCRT is important for subsequent therapy.

Patients And Methods: Patients were divided into two groups according to the nodal status, the complete response (CR) and the non-CR groups, as determined by imaging and fine-needle aspiration cytology (FNAC) performed 4-8 weeks after the CCRT, and the findings were compared with the status 6 months after the treatment completion.

Results: The sensitivity, the specificity, positive predictive value, negative predictive value and accuracy of each evaluation method were as follows: 66.7%, 73.5%, 26.7%, 93.8% and 72.5%, respectively, for computer tomography (CT) and magnetic resonance imaging (MRI); 91.7%, 69.9%, 30.6%, 98.3% and 72.6% for ultrasonography (US) ; 50.0%, 96.4%, 66.7%, 93.0% and 90.5% for fluorodeoxyglucose-positron emission tomography (FDG-PET) or PET-CT; and 68.4%, 96.1%, 81.3%, 92.5% and 90.6% for FNAC.

Conclusion: To evaluate the response of lymph node(s) treated by CCRT, US is useful as a positive screening tool and FDG-PET and PET-CT as negative screening tools. FNAC is useful in evaluating suspicious lymph nodes in both positive and negative cases.