An International Study of Malignant Transformation of Oral Leukoplakia

口腔白斑被认为是一种癌前病变，可发展为癌，频率为5%至10%。本研究的目的是通过比较日本和丹麦的口腔白斑病例，并应用哥本哈根大学和东京医科牙科大学于1997年合作制定的口腔白斑共同方案，阐明恶性转化的危险因素。在方案中，检查了年龄、性别、主诉、病程、部位、临床类型、烟草、酒精、上皮发育不良和念珠菌病等项目。我们调查了两个国家的协议。例如，我们病例中白斑的优先部位是龈舌和颊黏膜，而丹麦是颊黏膜、口腔底和牙龈。这种差异可能是由于习俗或环境因素造成的。检查这些差异并按照协议跟踪病例将有助于澄清白斑的高危人群。

Oral leukoplakia is considered to be a premalignant lesion and could develop carcinoma with a frequency ranging from 5 to 10 percent. The purpose of this study is to clarify risk factors for malignant transformation by comparing Japanese cases of leukoplakia with those in Denmark, applying a common oral leukoplakia protocol, which was made by collaboration between Copenhagen University and Tokyo Medical and Dental University in 1997. In the protocol, items such as age, sex, chief complaint, duration, site, clinical type, tobacco, alcohol, epithelial dysplasia and candidosis were examined. We investigated the protocols of two countries. For example, the preferential sites for leukoplakia of our cases are gingiva tongue, and buccal mucosa, however, those in Denmark are buccal mucosa, floor of the mouth and gingiva. Such differences may be due to customs or environmental factors. Examining such differences and Following cases by the protocol will contribute to clarification of high risk group of leukoplakia.