Prognostic influence of retropharyngeal lymph node metastasis in squamous cell carcinoma of the oropharynx

PURPOSE: To investigate the impact of involvement of retropharyngeal lymph nodes on the prognosis of squamous cell carcinoma of the oropharynx. METHODS AND MATERIALS: The pretreatment computed tomographic scans of 208 patients with squamous cell carcinoma of the oropharynx were reviewed for the presence of metastatic retropharyngeal lymph nodes. All patients were treated at the Leuven department between 1984 and 2003: by radiotherapy alone in 84.1% of patients, by surgery with postoperative radiotherapy in 11.5%, and by concomitant chemoradiotherapy in 4.4%. Retropharyngeal node involvement was present in 34 (16%) patients. The influence on recurrence (local and regional), distant metastasis, and survival was retrospectively analyzed. Median follow-up was 47 months (3.9 years), and results were analyzed for 201 patients. RESULTS: At 5 years, patients with retropharyngeal adenopathy had significantly more regional recurrences (45% vs. 10%, p = 0.004). Involvement of retropharyngeal lymph nodes significantly (relative risk 4.29 95% confidence interval 3.33-5.25], p = 0.01) and independently predicted regional recurrence in multivariate analysis. Disease-specific survival was significantly lower in the retropharyngeal node positive group (38% vs. 58%, p = 0.03). CONCLUSIONS: Retropharyngeal node involvement has a negative impact on the prognosis of squamous cell cancer of the oropharynx. Patients are particularly at risk for regional recurrence, resulting in worse disease-specific survival. Retropharyngeal node involvement should be taken into account in designing the treatment plan for these patients.