Minor salivary gland tumours. A retrospective study of 164 cases in a Brazilian population.

One hundred and sixty-four cases of intraoral salivary gland tumours retrieved from the files of the Surgical Oral Pathology laboratory of the University of São Paulo (Brazil), between 1970 and 1993, were studied. Of these, 164 tumours, 62% were classified as benign and 38% malignant. The palate was the main site of occurrence of the tumours followed by the buccal mucosa and upper lip. There was a slight predominance for female patients, with a female to male ratio of 1.3:1. The mean age for benign tumours was 39.9 years (40.8 for females, and 39.7 for males). For malignant tumours the mean age was 43.5 years (42.6 for females and 44.7 for males). Pleomorphic adenoma was the most common of the benign tumours, whereas mucoepidermoid carcinoma and adenoid cystic carcinoma were the most common malignant tumours. In general, benign tumours presented as an asymptomatic nodule. On the other hand, pain, ulceration and radiographic changes were more frequently associated with malignant lesions.