Adenoid cystic carcinoma: a third type of human salivary gland neoplasms characterized cytogenetically by reciprocal translocations.

Using G-banding technique, the chromosomes were studied in four consecutive preparations from cultured material from a human adenoid cystic carcinoma of the submandibular gland. The results indicated that the carcinoma had originated with a normal diploid stemline, and that reciprocal translocations played a predominant role in development of an abnormal stemline. The propensity of developing variant cells, as well as an abnormal stemline, characterized by various types of reciprocal translocations, was found to be a property shared by two other types of salivary gland neoplasms studied by banding techniques, namely the pleomorphic adenoma and the acinic cell tumour. The tissue of origin is suggested to be the crucial determinant responsible for this important cytogenetical similarity between different types of salivary gland tumours.