Lobular (polymorphous low-grade) carcinoma of minor salivary glands. A clinicopathologic study of twenty cases.

Twenty cases of a recently described adenocarcinoma of minor salivary gland--lobular carcinoma--are reviewed. This distinctive lesion occurs most frequently on the palate of patients in their sixth and seventh decades and displays no apparent sex or race predilection. Histomorphologically, the tumor is characterized by cytologic uniformity, bland nuclear chromatin, and low mitotic rate. Its lobular configuration and marked infiltrative tendency, often by single-filed tumor cells, are reminiscent of lobular carcinoma of the breast. Follow-up data indicate a favorable prognosis and are in accord with findings of previous investigators. The possible relationship of this lesion to adenoid cystic carcinoma is discussed.