Background: The objective of this study was to evaluate the effectiveness and safety of our careful observational strategy and neck dissections and the accuracy of ultrasound-guided fine-needle aspiration cytology, and to determine the prognostic factors for outcome and regional control after primary chemoradiation. Diagnostic evaluation of the regional status after concurrent chemoradiation for advanced head and neck cancer remains difficult, and the indications for a salvage neck dissection and its extent are not clearly defined.
Methods: In a series of 540 patients, there was suspicion of regional residual or recurrent disease after chemoradiation in 61 patients who underwent 68 salvage neck dissections and 68 patients who were considered unresectable. For the patients with salvage neck dissection, the accuracy of ultrasound-guided fine-needle aspiration cytology was determined. Disease control in the neck, disease-specific and overall survival, and parameters that may have prognostic value for the outcome were evaluated.
Results: Neck dissection specimens contained viable tumor in 26 (43%) patients. Of these, 13 had selective neck dissections and 13 modified radical neck dissections. Ultrasound-guided fine-needle aspiration cytology had a sensitivity of 80% and specificity of 42%. Nine patients developed a regional recurrence after salvage neck dissection (5 located in contralateral neck). Five-year regional control and overall survival rates were 79% and 36%, respectively. Significant prognostic factors for overall survival were surgical margins and "residual versus recurrent disease" in multivariate analysis.
Conclusion: Considering the good regional control rate and the high rate of unnecessary neck dissections with a theoretical planned neck dissection strategy, we conclude that a careful observational strategy is worthwhile and safe. For the evaluation of radiation treatment response, ultrasound-guided fine-needle aspiration cytology has a low specificity.