外阴上皮内瘤变组织中P16和Ki-67的表达及其意义

目的:探讨P16和Ki-67在外阴上皮内瘤变(VIN)组织中的表达及其意义。方法:采用免疫组化SP法检测44例VIN(VINⅠ16例,VINⅡ、Ⅲ28例)组织中P16和Ki-67的原位表达,并以30例正常外阴组织作为对照。结果:对照组、低级别VIN(VINⅠ)和高级别VIN(VINⅡ、Ⅲ)组织中P16的阳性率依次为7%、44%和100%,Ki-67的阳性率依次为10%、75%和100%;P16和Ki-67在VINⅡ、Ⅲ和对照组,VINⅡ、Ⅲ和VINⅠ之间的阳性表达率差异均具有统计学意义(P<0.01)。若将P16阳性表达界定为中和(或)上1/3外阴上皮细胞弥漫阳性着色、Ki-67阳性界定为下1/3外阴上皮以上大于或等于25%的上皮细胞胞核阳性着色,作为鉴别高级别VIN的标志物,P16的敏感性、特异性分别为93%、93%,Ki-67的敏感性、特异性分别为96%、85%。结论:P16和Ki-67在对照组、低级别VIN与高级别VIN组织中的表达有显著差异,可较敏感地鉴别出高级别VIN。采用二者联合标记,更能有效地降低假阳性病例的干扰,提高VIN诊断的特异性。

Expression and significance of P16 and Ki-67 in differential diagnosis of high-grade and non-high-grade vulvar intraepithelial neoplasia

Objective:To investigate the effects of P16 and Ki-67 on vulvar intraepithelial neoplasia(VIN).Methods: The expression of P16 and Ki-67 in situ in the lesion of 44 patients[16 low-grade VIN(VIN Ⅰ),and 28 high-grade VIN(VINⅡand Ⅲ)] were examined by immunohistochemical assay;and 30 normal vulvar tissues were treated as controls.Results: The positive percentages of P16 in normal vulvar tissues,VIN Ⅰ,Ⅱ,Ⅲ were 7%,44%,100% respectively;The positive percentages of Ki-67 in normal vulvar tissues,VIN Ⅰ,Ⅱ,Ⅲ were 10%,75%,100% respectively.The expressions of P16 and Ki-67 had significant differences between the high grade and low grade VIN(P<0.01).When positive P16 staining was defined as the presence of diffuse/continuous staining in more than one-third of the thickness of epithelium,the sensitivity and specificity of P16 as a marker for diagnosing high-grade VIN were 93%,93%,When positive Ki-67 staining was defined as the presence of nuclear staining in more than 25% of the cells in more than one-third of the thickness of epithelium,the sensitivity and specificity of Ki-67 as a marker for diagnosing high-grade VIN were 96%,85%.Conclusions: Both P16 and Ki-67 are reliable markers for diagnosing high-grade VIN.