Objective: To study the expression of Ki-67 and CK13 in oral leukoplakia(OLK) and to assess  its significance in diagnosis of oral dysplasia. Methods: A total of 50 cases of oral leukoplakia  were retrieved from department of oral pathology, stomatology hospital of Sichuan University. The immunohistochemical staining of Ki-67 protein and CK13 protein were used in above cases. Results: The number of positive expression of Ki-67 labeling cells presented in a positive correlation with the differentiation degree of the epithelial dysplasia from mild to severe (P<0.05).  Ki-67-immunopositive cells were spread throughout wider areas even in the whole epithelial layer in poor dysplasia cases. CK13 was strongly expressed in OLK without/with mild dysplasia. In most cases, the expression of CK13 in moderate and severe dysplasia was negative or weak. The expression of CK13 between OLK without/mild dysplasia and OLK with moderate/ severe dysplasia showed a significant difference statistically(P<0.05). Conclusion: Ki-67 and CK13 are useful markers for diagnosis  and grading OLK with epithelial dysplasia.

oral leukoplakia, grading of epithelial dysplasia, Ki-67, CK13

目的：国内外对口腔黏膜上皮异常增生的病理诊断和分级的认识存在严重分歧，其主观性较强，本研究探讨Ki-67及CK13在口腔黏膜白斑上皮异常增生组织中的联合表达，寻求口腔黏膜白斑上皮异常增生较为客观的病理辅助诊断分级指标。方法：收集口腔黏膜白斑50例，分析其临床病理特点。采用免疫组织化学S-P法检测Ki-67、CK13在伴有不同程度上皮增生的白斑中的表达情况，并对结果进行统计分析。结果：随着上皮异常增生程度的加重，Ki-67阳性细胞数增加（P<0.05）； Ki-67阳性细胞在上皮内分布范围扩大，甚至波及上皮全层。CK13在OLK不伴/伴轻度上皮异常增生中高表达。大多数OLK伴中、重度上皮异常增生，CK13呈阴性表达或弱阳性表达。CK13的表达在口腔黏膜白斑伴及不伴轻度上皮异常增生组与口腔黏膜白斑伴中、重度上皮异常增生组之间，差异有统计学意义（P<0.05）。结论：Ki-67、CK13的联合应用有助于口腔黏膜白斑上皮异常增生程度的判断，为病理诊断提供了较为客观的依据。