An International Study of Malignant Transformation of Oral Leukoplakia

口腔白斑被认为是一种癌前病变，可能发展为癌症，发生率从5%到10%不等。这项研究的目的是通过比较日本和丹麦的白斑病例，应用哥本哈根大学和东京医科大学于1997年合作制定的常见口腔白斑方案，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、上皮异常增生和念珠菌病。我们调查了两个国家的协议。例如，我们的白斑好发部位是牙周舌和颊粘膜，而丹麦的白斑好发部位是颊粘膜、口底和牙龈。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，并根据该方案跟踪病例，将有助于明确白斑的高危人群。

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.