[Clinical and histological studies of adenoid cystic carcinoma]. 
Forty-four salivary gland tumors were seen at The Center for Adult Diseases, Osaka, between 1979 and 1981; 30 were benign and 14 malignant.  Of the latter, 7 (50%) were adenoid cystic carcinoma (ACC).  Six of 7 ACC were reviewed with special attention to their histologic pattern, atypism, connective tissue around the cell nest, tumor cell nest, tumor cell invasion into lymphatics(ly) and blood vessels(v), and mitosis.  ACC was divided into 3 histological groups.  Patients with ly and/or v develop cervical and/or distant metastases at the early stage or during the follow-up period.  Ly and v were closely correlated with metastasis.