细胞角蛋白20免疫细胞化学染色辅助尿液基细胞学诊断尿路上皮癌的价值

Value of CK20 as an adjuvant to urine liquid-based cytology in detection of urothelial carcinoma

目的探讨细胞角蛋白20（CK20）的表达在辅助尿液基细胞学（LBC）诊断尿路上皮癌（UC）中的价值。方法采用前瞻性和回顾性研究两种方法。在前瞻性研究中，收集136例有泌尿系统症状患者和体检正常者尿液标本，进行尿LBC检查和CK20免疫细胞化学染色检测。在回顾性研究中，选取163例尿液细胞学档案中诊断为非典型尿路上皮细胞及更严重病变患者的液基薄片，脱色后进行CK20免疫细胞化学染色检测。以组织学诊断和临床随访结果作为金标准进行统计学分析。结果前瞻性研究中，UC89例，其他恶性肿瘤19例，良性病变12例，体检正常16例。CK20免疫细胞化学染色诊断UC的敏感性为75．3％，明显高于LBC（48．3％，P〈0．001）；特异性为91．5％，与LBC（91．5％）相同。CK20在G1、G2和G3级UC中的阳性表达率分别为64．7％（22／34）、73．3％（22／30）和91．3％（21／23），在G1和G2级UC中，CK20免疫细胞化学染色与LBC诊断的敏感性差异有统计学意义（G1级：P=0．0003，G2级：P=0．009）。回顾性研究中，UC119例，其他恶性肿瘤17例，良性病变27例。CK20在UC中的阳性表达率为90．8％，在非UC（良性病变和其他恶性肿瘤）中的阳性表达率为15．9％，差异有统计学意义（P〈0．001）。在119例UC中，LBC诊断癌62例（52．1％），可疑癌35例（29．4％），非典型尿路上皮细胞22例（18．5％）；CK20在LBC诊断为癌、可疑癌和非典型尿路上皮细胞中的阳性表达率分别为96．8％、97．1％和63．16％。在44例非UC中，LBC诊断癌6例（13．6％），可疑癌12例（27．3％），非典型尿路上皮细胞26例（59．1％）；CK20在LBC诊断为癌、可疑癌和非典型尿路上皮细胞中的阳性表达率分别为33．3％、33．3％和3．8％，与其在uc中的表达率差异均有统计学意义（均P〈0．001）。结论尿脱落细胞CK20免疫细胞化学染色可以辅助LBC提高诊断UC的敏感性。

Objective To investigate the value of cytokeratin 20 （CK20） immunocytochemical （ICC） detection in the urine liquid-based cytological specimens in diagnosis of urothelial carcinoma （UC）. Methods The study consisted of prospective and retrospective groups. In the prospective group, voided urine samples were collected from patients with a variety of urological conditions and healthy individuals. Urine cytological diagnosis and CK20 ICC were performed on the collected specimens. In the retrospective group, archived urine slides with cytological diagnoses of atypical urothelial cells （AUC）, suspicious carcinoma （SuCA） and carcinoma （CA） were selected. Then they were re-stained immunocytochemically with monoclonal antibody against CK20 after decolorization. Histological diagnosis and clinical follow-up result were used as the gold standard for analysis. Results There were 136 cases in the prospective group, including 89 cases of UC, 19 cases of other urogenital malignancies, 12 cases of benign lesions and 16 cases of normal control. The sensitivity of CK20 ICC in detection of UC was 75.3% , significantly higher than that of LBC （48.3%, P 〈0.1301 ）. The positive rate of CK20 was 64.7% （22/34） in G1 UC, 73.3% （22/30） in G2 UC, and 91.3% （21/23） in G3 UC （ P 〈 0.001 ）. The specificity of CK20 ICC was 91.5% , the same as that of LBC. There were 163 cases in retrospective group, including 119 cases of UC, 17 cases of other urogenital malignancies and 27 cases of benign lesions. The cytological diagnoses of them were 68 cases of CA, 47 eases of SuCA and 48 cases of AUC. The positive rates of CK20 ICC in UC and non-UC （ other urogenital malignancies and benign lesions） cases were 90.8% and 15.9% , respectively, with a statistically very significant difference （P〈0.001）. The LBC of all the 119 eases of UC included 62 （52.1%） cases of CA, 35 （29.4%） cases of SuCA and 22 （18.5%） cases of AUC. The positive rates of CK20 in the LBC- diagnosed CA, SuCA and AUC were 96.8%, 97.1% and 63.6% , respectively. The LBC of all the 44 non- UC cases included 6 （ 13.6% ） cases of CA, 12 （27.3%） cases of SuCA and 26 （59.1%） cases of AUC, and the positive rates of CK20 in the LBC-diagnosed CA, SuCA and AUC were 33.3% , 33.3% and 3.8% , respectively. The differences of UC and non-UC cases between the corresponding categories of LBC were significant （P 〈 0.0001, respectively）. Conclusion CK20 immunocytochemistry as an auxiliary method to urine liquid-based cytology can increase the sensitivity in detection of urothelial carcinomas.