Salivary gland adenoid cystic carcinoma with cervical lymph node metastasis: a preliminary study of 62 cases.

Adenoid cystic carcinoma (ACC) is an infrequent malignant neoplasm that originates most commonly in the major and minor salivary glands of the head and neck region. This study provides new information on head and neck ACC with cervical lymph node metastasis. Of 616 patients who underwent primary tumour resection from 1995 to 2008 in the authors' hospital, 62 cases with cervical lymph node metastasis were analyzed. The general incidence of cervical lymph node metastasis in ACC was approximately 10%. The base of tongue, mobile tongue and mouth floor were the most frequent sites of lymph nodes metastasis, with incidences of 19.2%, 17.6% and 15.3%, respectively. Most cases occurred via a classic 'tunnel-style' metastasis and the level Ib and II regions were the most frequently involved. Primary site and lymphovascular invasion were significantly associated with lymph node metastasis. High patient mortality was significantly correlated with lymph node positive cases. The tongue-mouth floor complex has a high propensity for cervical lymph node metastasis, which occurs through a classic 'tunnel-style' metastasis. Peritumoral lymphovascular invasion could be taken as strong predictor for lymph node metastasis, which ultimately leads to poor prognosis of ACC patient. Selective neck dissection should be considered in such cases.