Role of planned neck dissection for advanced metastatic disease in tongue base or tonsil squamous cell carcinoma treated with radiotherapy

Objective: At the conclusion of this article, the reader should be able to discuss the need for planned neck dissection for advanced cervical diseases in the tongue base and tonsil cancer after treatment with radiotherapy.

Background: In the past 5 years, we have treated patients with squamous cell carcinoma of the tonsil and tongue base with radiotherapy as the primary therapeutic modality. A planned complete neck dissection was performed on all patients with N2 or greater cervical disease regardless of response to radiotherapy. Composite resection was performed when there was persistent disease at the primary site. Although the "radiation-first" therapeutic approach for tongue base and tonsil cancer is widely accepted, the planned neck dissection for neck metastases remans controversial. The objective of the study was to determine the validity of planned neck dissection after radiotherapy for N2 disease.

Methods: Medical records of patients with primary squamous cell carcinoma of the tongue base and tonsil with neck metastasis staged N2 or greater were reviewed. Between 1994 and 1999, 36 such patients were treated with curative radiation therapy. Response was assessed 6 to 8 weeks after completion of treatment with clinical examination and CT imaging. All patients underwent planned neck dissection. We reviewed the clinical and radiographic response of neck disease to radiotherapy as it correlated with the histopathologic findings.

Results: Of the 36 patients, 17 had clinical and CT evidence of persistent disease. In this group, 65% had pathologically confirmed diseases at surgery. Of the 9 patients with no evidence of disease on clinical examination, negative biopsy at the primary site, and a negative CT scan, 33% (three of nine) still had residual disease in the neck dissection specimen.

Conclusions: Positive findings on clinical examination and CT can predict the presence of malignancy after radiation therapy. However, a negative CT and clinical examination are limited in predicting a complete response. These data lend support to the role of planned neck dissection after radiotherapy of N2 neck disease.