Effectiveness of selective neck dissection in head and neck cancer: the experience of two Italian centers.

OBJECTIVE The aim of this study was to evaluate the oncologic outcomes after a selective neck dissection (SND), both in elective and therapeutic settings, with particular regard to regional recurrence rate. METHODS Retrospective analysis of 827 patients with head and neck primary tumors submitted to SND from 1999 to 2011 in two large hospital centers of northern Italy. RESULTS A total of 40 neck recurrences were found in the whole series, with the same incidence after primary or salvage surgery (4.4% and 5.2%, respectively), but only 22 neck recurrences occurred in the same side of the dissected neck (3.0%). Factors predicting an increase of ipsilateral neck relapse were pathologically positive nodes, number of positive nodes, and nodal ratio (ratio between positive nodes and total nodal removed), but the risk of regional relapse did not exceed 5.0% in any subgroups. A total of 320 patients (39%) had postoperative radiotherapy (52.0% and 22.0% after primary and salvage surgery, respectively). Considering the primary surgery group alone, postoperative radiotherapy produced only a light reduction of homolateral neck recurrence rate in patients with pathological positive nodes (2.4% vs. 5.0%), but it impacted significantly disease-specific survival, both in pathological classification of nodes (pN)1 and pN2-3 patients. CONCLUSION The SND can be considered a safe and sound procedure both in primary surgery and in salvage setting. Postoperative radiotherapy adds minor advantage to regional control only in node-positive patients but may impact survival. LEVEL OF EVIDENCE 4.