p16、Ki-67双染在子宫颈上皮内病变病理诊断和分级中的应用

目的: 探讨p16 和Ki-67免疫组织化学（免疫组化）双染在子宫颈（以下简称宫颈）上皮内病变病理诊断和分级中的应用价值。方法: 应用免疫组化双染检测15例子宫颈不成熟鳞状化生(immature metaplasia,IM)、32例低级别鳞状上皮内病变即子宫颈上皮内瘤变Ⅰ级（cervical intraepithelial neoplasia Ⅰ,CINⅠ）、90例高级别鳞状上皮内病变即CIN Ⅱ和CIN Ⅲ患者的病理组织中p16 和Ki-67蛋白的共表达情况,分析其与宫颈上皮内病变临床病理诊断及分级间的关系。结果: 在单染切片中,p16在IM组织中呈阴性;在CIN Ⅰ组织中呈不连续、片状或斑片状分布,阳性强度弱,阳性细胞分布于鳞状上皮层下1/3;而在CIN Ⅱ和CIN Ⅲ组织中呈鳞状上皮中下2/3甚至全层连续、弥漫强阳性,p16在IM及CIN Ⅰ~Ⅲ组织中的阳性率分别为6.67%、62.50%、88.89%、95.56%,4组间比较差异有统计学意义(P<0.05)。Ki-67在IM组织中主要表达于鳞状上皮基底层和旁基底层;在CIN Ⅰ组织中则主要表达于鳞状上皮层的下1/3;在CIN Ⅱ、CIN Ⅲ组织中Ki-67阳性细胞可分布于鳞状上皮的中下2/3甚至全层,IM及CIN Ⅰ~Ⅲ组织中Ki-67指数均值分别为7.21%、16.41%、33.54%、50.32%,4组间比较差异有统计学意义(P<0.05)。在双染切片中,双染不会导致Ki-67阳性信号的缺失,p16阳性区域中,Ki-67指数均值为36.47%;p16阴性区域中,Ki-67指数均值为10.53%,且随着宫颈上皮内病变级别增加,p16和Ki-67共表达的例数逐渐增多, 在IM、CIN Ⅰ级、CIN Ⅱ级、CIN Ⅲ级组织中共表达率分别为0、51.35%、85.45%、99.42%,组间比较差异有统计学意义（P<0.05）。结论: p16、Ki-67在子宫颈鳞状上皮内病变中的共表达与 CIN 级别呈正相关,免疫组化双染对宫颈上皮内病变的诊断和分级具有重要价值。

The use of p16/Ki-67 double-staining in diagnosis of cervical intraepithelial lesion

Objective: To investigate the role of p16/Ki-67 double-staining in diagnosis and grading of cervical intraepithelial lesions. Methods: Immunohistochemical dual stain was used to detect the co-expression of p16 and Ki-67 in 15 cases of cervical immature metaplasia (IM), 32 cases of low-grade squamous intraepithelial lesion（LSIL, CIN Ⅰ）, 90 cases of high-grade squamous intraepithelial lesion (HSIL, CIN Ⅱ and CIN Ⅲ). The correlation of p16 and Ki-67 co-expression with diagnosis and grading of cervical intraepithelial lesion was analyzed. Results: p16 was negative in IM, and was of focal or patchy staining with weak intensity and positive cells restricted to the lower third of squamous epithelium in CIN Ⅰ. In HSIL, diffuse p16 positive immunostaining cells of 2/3 or full thickness of squamous epithelium was seen. The positive rates of p16 protein were 6.67%, 62.50%,88.89%, 95.56% in IM, CIN Ⅰ, CIN Ⅱ,CIN Ⅲ, respectively, and the differences between these 4 groups were statistically significant (P<0.05). For Ki-67, expression only existed in the basal or parabasal cells in IM. In CIN Ⅰ, Ki-67 immunostaining was restricted to the lower third of the squamous epithelium, while diffuse Ki-67 immunostaining in 2/3 or full thickness of the squamous epithelium was seen in HSIL. The Ki-67 indices were 7.21%, 16.41%, 33.54%, 50.32% in IM,CIN Ⅰ, CIN Ⅱ, CIN Ⅲ, respectively, and the differences were statistically significant (P<0.05). Dual staining did not lead to the absence of Ki-67-positive signal. Ki-67 index was 36.47% in p16 positive region, while was 10.53% in p16 negative region. With the increase in grading of cervical epithelial lesion, the cases of p16/Ki-67 co-expression increased. The co-expression rates of p16/Ki-67 were 0, 51.35%, 85.45%, 99.42% in IM、CIN Ⅰ、CIN Ⅱ、CIN Ⅲ, respectively (P<0.05). Conclusions: The expression of p16 and Ki-67 is associated with the increase in grading of cervical squamous intraepithelial lesion. There is a significantly positive correlation between the expression of p16 and Ki-67. Immunohistochemical dual staining is helpful for the diagnosis and grading of cervical intraepithelial lesions.