Golijanin D, Shapiro A, Pode D
Department of Urology, Hadassah Medical Center, The Hebrew University Medical School, Jerusalem, Israel.
J Urol. 2000 Dec;164(6):1922-5.
Cytokeratin 20 is a cytoskeletal protein expressed in colon and bladder cancer cells but only rarely in normal urothelium. Previous studies have shown that identification of RNA coded for cytokeratin 20 in urine samples using polymerase chain reaction is highly sensitive for detection of bladder tumors. We examined the efficacy of immunocytology on cells from voided urine samples using monoclonal antibodies against cytokeratin 20 for noninvasive detection of bladder tumors.
A total of 174 patients comprised the study, including 80 who were evaluated because of hematuria or irritative voiding symptoms and 94 who were examined during followup visits after resection of bladder tumors. Voided urine samples were obtained for immunocytology and cytopathology. Each patient underwent cystoscopy, and biopsies were done when a bladder tumor was detected or carcinoma in situ was suspected. Indirect immunoperoxidase staining was done on cytocentrifuge slides using a monoclonal antibody against cytokeratin 20.
Bladder tumors were found in 87 patients. Immunocytology resulted in 81.6% sensitivity, 77% specificity and 80% accuracy. False-negative results occurred in 12 patients with superficial low grade tumors and in 4 with high grade invasive tumors. Cytopathology resulted in 51.7% sensitivity and 94.2% specificity.
Immunocytology of the cytokeratin 20 antigen is significantly more sensitive than cytopathology for bladder tumor detection, especially low grade and low stage cancer. The results are not affected by inflammation or previous treatments with bacillus Calmette-Guerin. Immunocytology may miss high grade tumors and, therefore, cannot be used alone as a substitute for cystoscopy.
细胞角蛋白20是一种细胞骨架蛋白，在结肠和膀胱癌细胞中表达，但在正常尿路上皮中很少表达。先前的研究表明，使用聚合酶链反应鉴定尿样中编码细胞角蛋白20的RNA对膀胱肿瘤的检测具有高度敏感性。我们使用抗细胞角蛋白20的单克隆抗体，检测了对来自晨尿样本的细胞进行免疫细胞学检查用于膀胱肿瘤无创检测的效果。
共有174例患者纳入本研究，其中80例因血尿或刺激性排尿症状接受评估，94例在膀胱肿瘤切除术后的随访期间接受检查。获取晨尿样本用于免疫细胞学和细胞病理学检查。每位患者均接受膀胱镜检查，当检测到膀胱肿瘤或怀疑有原位癌时进行活检。使用抗细胞角蛋白20的单克隆抗体对细胞离心涂片进行间接免疫过氧化物酶染色。
87例患者发现膀胱肿瘤。免疫细胞学检查的敏感性为81.6%，特异性为77%，准确性为80%。12例浅表低级别肿瘤患者和4例高级别浸润性肿瘤患者出现假阴性结果。细胞病理学检查的敏感性为51.7%，特异性为94.2%。
细胞角蛋白20抗原的免疫细胞学检查在膀胱肿瘤检测方面比细胞病理学检查明显更敏感，尤其是低级别和低分期癌症。结果不受炎症或先前卡介苗治疗的影响。免疫细胞学检查可能会漏诊高级别肿瘤，因此不能单独用作膀胱镜检查的替代方法。
