Introduction: Metastatic spread to parotid-area lymph nodes (PALN) occurs in 1% to 3% of patients with cutaneous squamous cell carcinoma of the head and neck. Presented herein is the University of Florida experience using radiation therapy (RT) to treat patients with PALN metastases from a skin primary.
Methods and materials: From November 1969 to February 2005, 121 parotids in 117 patients received irradiation for nonmelanotic skin carcinoma metastatic to PALN. Patients were staged by the O'Brien staging system. Of the 121 parotids receiving RT, 17 (14%) were treated preoperatively, 87 (72%) postoperatively, and 17 with RT alone.
Results: Five-year actuarial probabilities of local (parotid) control, local-regional control, disease-free survival and overall survival were 78%, 74%, 70%, and 54%, respectively. When patients were separated by O'Brien P-stage, statistically significant differences were seen among the groups for local (parotid) control, local-regional control, and disease-free survival. A statistically significant decrease in local control was seen in patients treated with positive surgical margins (92% vs. 76%) and in local-regional control for patients treated with preoperative RT or RT alone when compared with postoperative RT (59% and 47% vs. 83%, respectively). The 5-year actuarial probability of freedom from distant metastases was 92%. Three (2.6%) patients suffered severe complications.
Conclusions: PALN metastases from a cutaneous head and neck primary site are best treated with surgery and postoperative RT. Our data support the hypothesis that the O'Brien staging system is superior to the American Joint Committee on Cancer system for the staging of cutaneous metastases to PALN. Positive surgical margins confer a worse prognosis in terms of local-regional control and disease-free survival. Patients treated with preoperative RT seem to have a worse prognosis than those treated postoperatively, likely a result of patient selection and the surgeon's inability to accurately assess viable tumor extent after preoperative RT. Severe complications are uncommon after surgery and RT for PALN metastases.