Neck dissection for unknown cancer of the head and neck in the era of chemoradiation

Purpose

To report outcomes for patients with cervical lymph node metastases from an unknown primary site of the head and neck treated with either non-operative therapy or neck dissection followed by adjuvant therapy.

Materials and Methods

All patients with squamous cell carcinoma of an unknown primary site of the head or neck seen between 2003 and 2013 were reviewed. The Kaplan-Meier method was used to estimate overall survival, local recurrence free survival, loco-regional recurrence free survival, and progression free survival. The log-rank test and proportional hazards regression were used to analyze factors influencing outcomes.

Results

Of 2258 patients with a new diagnosis of head and neck cancer, no primary site was identified in 66 patients. Twenty-nine patients were treated with definitive non-operative therapy (15 with chemoradiation and 14 with radiation alone). Thirty-seven patients received an upfront neck dissection followed by adjuvant radiation or chemoradiation. Three-year loco-regional recurrence free survival, progression free survival, and overall survival were 55.9%, 55.4%, and 69.4% respectively. Patients treated with preoperative neck dissection had improved local recurrence free survival (96.7% vs 54.1%, p = 0.003) and loco-regional recurrence free survival (82.2% vs 46.4%, p = 0.068) compared to patients treated with definitive chemoradiation with no difference in overall survival (p = 0.641).

Conclusions

Neck dissection improved local and regional control but not overall survival in patients with unknown primary squamous cell carcinoma of the head and neck over non-operative therapy alone.