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Lymph node dissection for head and neck cancer.

A retrospective analysis of 141 neck dissections performed at the Royal Melbourne Hospital from 1975 to 1981 has been carried out with a view to identifying the prognostic factors. When a neck dissection is performed, the site of the primary disease did not affect the 5 year survival rate. A conservation neck dissection, especially when performed electively, had the best prognosis. Radiotherapy did not affect the overall survival rate in patients having a neck dissection, while chemotherapy appeared to exert a beneficial effect on patients with advanced disease. While clinical nodal staging was an important prognostic indicator, the number of nodes pathologically involved was not. Histologic differentiation of the tumour was not prognostically significant, whereas extracapsular nodal disease was. Most (70%) treatment failures occurred in the neck, while systemic metastases occurred in 12% of patients.