Clinical characteristics of oral adenosquamous carcinoma: report of a case and an analysis of the reported Japanese cases.

We present a case of adenosquamous carcinoma (ASC) which developed in the floor of the mouth of a 72-year-old Japanese man, and review 19 reported ASC cases in Japan from between 1986 and 2001, including the subject case herein. These ASCs occurred at an average age of 63 years, with 74% of the ASCs occurring in the floor of the mouth (8) and the tongue (6); the other sites of occurrence were the palate (3) and mandibular alveolus (2). Chief complaints were painless mass formation (28%), pain and/or sensational abnormality (28%), painful ulcer or swelling (22%), simple ulcer (11%), and miscellaneous others (11%). The clinical presentations of ASC were tumor with ulceration (58%), tumorous mass (26%), and ulcer (16%). Tumor size at first examination varied from bean-size to approximately 65 x 40 mm. In the pretreatment period, 31.3% were known to have cervical lymph node involvement, and descriptions on distant metastasis were not noted in any of the 19 cases. Some of the ASCs were initially diagnosed as other types of lesions, such as squamous cell carcinoma (SCC; 41%), adenocarcinoma (Ad.C; 12%) mucoepidermoid carcinoma (MEC; 6%), and MEC or SCC (6%). After initial treatments, neck and distant metastases were ascertained in 47.1 and 17.6% of the cases, respectively. Generally, a surgical procedure was performed as one of the most critical methods of treatment. The overall 5-year survival rate was 57.0%, with that of patients who underwent active treatment at 60.6%. Our study demonstrates the extent of the varied nature of ASC.