The node-negative neck: accuracy of clinical intraoperative lymph node assessment for metastatic disease in head and neck cancer

OBJECTIVES/HYPOTHESIS: Often, the type of neck dissection performed in patients with head and neck malignancy is finally determined by intraoperative assessment of clinically suspect lymph nodes by frozen section. This prospective study aimed to assess the accuracy of clinical intraoperative lymph node assessment and therefore to examine validity of the underlying assumption that the surgeon can consistently identify nodes that contain metastatic tumor. We also aimed to assess whether gross morphological characteristics of the lymph nodes examined could be correlated with nodal status and therefore used to predict those nodes containing metastatic disease. STUDY DESIGN: A prospective study assessing the accuracy of clinical intraoperative lymph node assessment in the node-negative neck. METHODS: Forty-six neck dissections from 34 patients with head and neck cancer were prospectively examined intraoperatively by a single surgeon. All obvious nodes were clinically assessed, morphologically described, and subsequently correlated with pathological findings. RESULTS: Sixty palpable nodes were identified in 32 neck dissections. They were clinically categorized as malignant or suspect (22) or benign (38). Pathological examination revealed a false-positive rate of 30% and a false-negative rate of 44%. The sensitivity of intraoperative lymph node assessment was 56%, and the specificity was 70%. Apart from "infiltration," morphological characteristics could not be correlated with nodal status. In the 14 neck dissections with no obviously palpable lymph nodes, 4 (29%) were positive for metastatic disease. CONCLUSIONS: In the node-negative neck, intraoperative assessment does not seem to improve the accuracy of staging. The only parameter of benefit and correlating with metastatic disease is clinical evidence of infiltration. The assumption that frozen section is a good determinate for selection of type of neck dissection is questionable. If selective neck dissection is not found to be therapeutic, its use leads to over-reliance on other therapeutic treatment such as postoperative radiotherapy, depriving the patient of a potential useful treatment modality in cases of locoregional recurrence.