p16^INK4a免疫细胞化学染色在子宫颈癌筛查中的应用价值

Clinical value of p16^INK4a immunocytochemistry in cervical cancer screening

目的探讨p16^INK4a免疫细胞化学染色(p16^INK4a染色)作为新一代子宫颈细胞学检查技术在人群子宫颈癌初筛与辅助常规细胞学检查及高危型(HR)-HPV初筛后的二次筛查中的价值。方法募集2016—2018年深圳及周边地区25~65岁有性生活的非妊娠期妇女5747例,采用HR-HPV联合子宫颈液基细胞学检查(LCT)进行子宫颈癌初筛;并行p16^INK4a染色,其中902例在初筛的同时进行p16^INK4a染色,其余4845例为HR-HPV与LCT初筛阳性回叫行阴道镜检查时取样进行p16^INK4a染色。将具有完整LCT检查、HR-HPV检测、p16^INK4a染色及子宫颈活检后病理诊断结果者纳入本研究。以组织学病理诊断为“金标准”,评价p16^INK4a染色作为子宫颈癌初筛、辅助LCT检查及HR-HPV初筛后的二次分流方案检出子宫颈病变[即高级别鳞状上皮内病变(HSIL)],包括HSIL[子宫颈上皮内瘤变(CIN)Ⅱ]及以上级别病变[HSIL(CINⅡ)+]、HSIL(CINⅢ)及以上级别病变[HSIL(CINⅢ)+]的筛查效率。结果(1)具有完整LCT检查、HR-HPV检测、p16^INK4a染色及子宫颈活检病理诊断结果者共1097例,纳入本研究。病理诊断:正常子宫颈995例,低级别鳞状上内病变(LSIL)37例、HSIL 64例及子宫颈癌1例,其中HSIL(CINⅡ)+65例,HSIL(CINⅢ)+34例。HSIL(CINⅡ)+患者的p16^INK4a阳性率(89.2%,58/65)显著高于CINⅠ或正常子宫颈者(10.2%,105/1032;P<0.01)。(2)p16^INK4a染色作为初筛方案:与HR-HPV检测比较,p16^INK4a染色检出HSIL(CINⅡ)+、HSIL(CINⅢ)+的敏感度均无显著差异(95.4%与89.2%,94.1%与94.1%;P>0.05),但其特异度均显著增高(82.5%与89.8%,80.2%与87.7%;P<0.05);而与LCT结果≥LSIL比较,p16^INK4a染色检出HSIL(CINⅡ)+、HSIL(CINⅢ)+的敏感度、特异度均无显著差异(P>0.05)。(3)p16^INK4a染色辅助LCT检查:与单独LCT检查或HR-HPV检测辅助LCT检查比较,p16^INK4a染色辅助LCT检查检出HSIL(CINⅡ)+、HSIL(CINⅢ)+的特异度均显著增高(P<0.01),而敏感度均无显著差异(P>0.05)。(4)p16^INK4a染色作为二次分流方案:HR-HPV初筛后以p16^INK4a阳性作为二次分流指标与LCT结果≥ASCUS作为二次分流指标比较,检出HSIL(CINⅡ)+、HSIL(CINⅢ)+的敏感度均无显著差异(84.6%与90.8%,88.2%与91.2%;P>0.05),而特异度均有显著差异(94.1%与89.7%,91.9%与87.4%;P<0.01);作为二次分流方案,HPV 16和(或)18型(HPV 16/18型)阳性与p16^INK4a阳性序贯的方案,HPV 16/18型阳性与LCT结果≥ASCUS序贯的方案,两种方案比较,检出HSIL(CINⅢ)+的敏感度无显著差异(分别为88.2%、94.1%,P=0.500),而前者的特异度显著增高(分别为88.3%、83.0%,P<0.01),且前者的阴道镜转诊率显著降低(分别为14.0%、19.4%,P=0.005)。结论p16^INK4a染色作为子宫颈癌初筛方案检出子宫颈病变的敏感度与HR-HPV检测相当、特异度与LCT检查相当;且在HR-HPV阳性患者的二次分流中具有优势,并可辅助LCT检查进行诊断分级,提高了子宫颈细胞学筛查的准确率。

Objective To evaluate the value of p16^INK4a detected by p16^INK4a immunostaining as a new generation of cervical cytology for primary screening and secondary screening in population-based cervical cancer screening,and in improving cytological diagnosis.Methods Between 2016 and 2018,5747 non-pregnant women aged 25-65 years with sexual history were recruited and underwent cervical cancer screening via high-risk(HR)-HPV/liquid-based cytological test(LCT)test in Shenzhen and surrounding areas.All slides were immuno-stained using p16^INK4a technology,among them,902 cases were offered p16^INK4a detection during primary screening,and the remaining 4845 cases were called-back by the virtue of abnormal HR-HPV and LCT results for p16^INK4a staining.Participants with complete LCT examination,HR-HPV test,p16^INK4a staining and histopathological examination results were included in this study.The performance of p16^INK4a in primary and secondary screening,and in assisting cytology to detect high grade squamous intraepithelial lesion[HSIL,including cervical intraepithelial neoplasia(CIN)ⅡorⅢ]or worse[HSIL(CINⅡ)+or HSIL(CINⅢ)+]were analyzed.Results(1)One-thousand and ninety-seven cases with complete data of p16^INK4a and histology were included.Pathological diagnosis:995 cases of normal cervix,37 cases of low grade squamous intraepithelial lesion(LSIL),64 cases of HSIL and one case of cervical cancer were found.Among them,65 cases of HSIL(CINⅡ)+and 34 cases of HSIL(CINⅢ)+were detected.The positive rate of p16^INK4a in HSIL(CINⅡ)+was higher than that in CINⅠor normal pathology(89.2%vs 10.2%;P<0.01).(2)p16^INK4a as primary screening for HSIL(CINⅡ)+or HSIL(CINⅢ)+was equally sensitive to primary HR-HPV screening(89.2%vs 95.4%,94.1%vs 94.1%;P>0.05),but more specific than HR-HPV screening(89.8%vs 82.5%,87.7%vs 80.2%;P<0.05).p16^INK4a was equally sensitive and similarly specific to cytology(≥LSIL;P>0.05).(3)The specificity of LCT adjunctive p16^INK4a for detecting HSIL(CINⅡ)+or HSIL(CINⅢ)+were higher than that of LCT alone or adjunctive HR-HPV(P<0.01),while the sensitivity were similar(P>0.05).(4)p16^INK4a staining as secondary screening:p16^INK4a was significantly more specific(94.1%vs 89.7%,91.9%vs 87.4%;P<0.01)and comparably sensitive(84.6%vs 90.8%,88.2%vs 91.2%;P>0.05)to cytology for triaging primary HR-HPV screening.HPV 16/18 to colposcopy and triage other HR-HPV with p16^INK4a was equally sensitive(88.2%vs 94.1%;P=0.500)and more specific(88.3%vs 83.0%;P<0.01)than HPV 16/18 to colposcopy and triage other HR-HPV with LCT≥atypical squamous cells of undetermined significance(ASCUS),and the referral rate decreased(14.0%vs 19.4%;P=0.005).Conclusions For primary screening,p16^INK4a is equally specific to cytology and equally sensitive to HR-HPV screening.p16^INK4a alone could be an efficient triage after primary HR-HPV screening.In addition,p16^INK4a immunostaining could be used as an ancillary tool to cervical cytological diagnosis,and improves its accuracy in cervical cancer screening.