Diagnostic performance of core needle biopsy for nodal recurrences in patients with head and neck squamous cell carcinoma.

This study investigated the diagnostic accuracy and affecting factors of ultrasound (US)-guided core-needle biopsy (CNB) in patients with treated head and neck squamous cell carcinoma (HNSCC). We retrospectively reviewed patients with treated HNSCC who received US-guided CNB from January 2011 to December 2018 with corresponding imaging. Pathological necrosis and fibrosis of targeted lymph nodes (LNs) were evaluated. We analyzed the correlation between CNB accuracy and clinical and pathological characteristics. In total, 260 patients were included. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of CNB for nodal recurrence were 84.47%, 100%, 100%, 54.67%, and 86.92%, respectively. CNB of fibrotic LNs had significantly worse sensitivity, NPV, and accuracy than that of non-fibrotic LNs. Similarly, CNB of necrotic LNs had significantly worse sensitivity, NPV, and accuracy than non-necrotic LNs. Multivariate regression revealed that fibrotic LN was the only independent factor for a true positive rate, whereas both necrotic LN and fibrotic LN were independent factors for a false negative rate. The diagnostic accuracy of CNB in treated HNSCC patients is affected by LN necrosis and fibrosis. Therefore, CNB results, particularly for necrotic or fibrotic LNs, should be interpreted carefully.