口腔内多発癌の臨床的検討

Oral cancer

北海道歯学会

北海道歯学雑誌

In this study 22 patients with multiple primary oral cancers (out of 373 oral squamous cell carcinoma) were observed. These patients were treated at Oral Surgery of Hokkaido University Hospital from 1984 to 2011. 3 synchronous, 10 metachronous and 9 synchro-metachronous carcinomas were observed. The buccal mucosa, lower gingiva, tongue, upper gingiva were seen frequently. The mean interval between the first and the second carcinomas was 80.6 months, while that between the second and third carcinomas was 82.5 months. 　Surgical treatment was performed for most cases. Local recurrence rate was 50.7% and cervical lymph node metastasis rate was 59.1%. The 5-year and the 10-year disease-specific cumulative survival rate were 81.8% and 50.3%, respectively. The long developmental period, high local recurrence and regional metastasis indicate the necessity of a long term followup and maintenance of good oral environment to inhibit tumor pathogenesis.