Abstract

We studied 1809 oral cancer patients who visited and were treated in 2002 at the 148 institutions certified as training facilities by the Japanese Society of Oral and Maxillofacial Surgeons, which is composed of 39 dental university hospitals, 44 medical university hospitals, 64 general hospitals, and 1 unknown institution. The patients consisted of 1071 (59.2%) males and 738 (40.8%) females (male:female ratio, 1.45:1), who had a mean age of 65.2 years old. The tongue (40.2%) was the most common site affected, followed by the gingiva (32.7%), buccal mucosa (10.1%), and oral floor (9.0%). There were 6 cases of intraoral multiple cancer. In histopathological examinations, squamous cell carcinoma (88.7%) was the most common type found, followed by adenoid cystic carcinoma (2.1%), and mucoepidermoid carcinoma (1.7%). In addition, non-epithelial tumors comprised 1.8%, among which malignant melanoma was the most common type. Cases classified as T2N0 were the most common (32.1%), followed by T1N0 (21.4%), T4N0 (8.0%), and T2N1 (7.6%). Distant metastasis occurred in 17 patients (1.0%). The sizes of the non-epithelial malignant tumors ranged from 1.0 to 7.0 cm, with a mean size of 3.7 cm.