Lymph node metastasis and neck dissection for parotid cancer : Investigation of 194 cases

Abstract

There is no consensus about the indications and range of neck dissection for parotid cancer. In particular, elective neck dissection （END） for clinically N0 cases is still controversial. Fifty-one among 194 patients had lymph node metastasis, including 6.9％, 12.0％, 35.7％, and 53.7％ of patients with T1, T2, T3, and T4 disease, respectively. As to histological grade, 6.4％ of patients with low/intermediate-grade versus 52.4％ of patients with high-grade had lymph node metastasis. We have performed END for clinically N0 patients, and occult metastasis was found in 9 out of 79. The most common site of metastasis was level Ⅱ, followed by the periparotid nodes and levelⅢ. The disease-specific 5-year survival rate for the N classification was 88.1％, 75.0％, and 32.9％ in patients with N0, N1, and N2 disease, respectively. END may be most appropriate for high-grade parotid carcinoma with an advanced T classification. Because preoperative grade evaluation has limited reliability, it is important to decide the indications and range of neck dissection from the results of frozen section biopsy.