Safadi Rima A, AlRomaizan Abdulaziz, Alshagroud Rana S, Divakar Darshan D, Alshieban Saeed
Faculty of Dentistry, Jordan University of Science and Technology, P.O Box: 3030, Irbid, 22110, Jordan.
King Saud bin Abdul Aziz University for Health Sciences, P.O Box: 22490, Riyadh, 11426, Saudi Arabia.
Head Neck Pathol. 2020 Mar;14(1):183-191. doi: 10.1007/s12105-019-01038-w. Epub 2019 May 14.
Epithelial dysplasia (ED) grading systems are criticized for low reliability. The effects of diagnostic tests or stains on reducing examiner variability in grading ED of the upper aerodigestive tract have not been investigated. The study aim was to examine the effectiveness of cytokeratin 19 (K19) immunostain on enhancing inter and intraexaminer reliability of ED grading and to reiterate the relation of K19 positivity with epithelial keratinization. The study sample consisted of 122 paraffin blocks that fulfilled the inclusion criteria. Each paraffin block had three sections cut: one immunostained for K19 and two for hematoxylin and eosin stain (H&E). Each examiner graded the study sample in six rounds; three using H&E stain only and three using paired K19-H&E stains. The study examiners were three American-Board certified practicing oral pathologists. The results were analyzed using Krippendorff's alpha, ROC curve, Chi square test and binary logistic regression. Upon the use of paired K19-H&E stains the results showed that the intraexaminer reliability coefficients of grading were improved from 0.70, 0.69, 0.78 to 0.73, 0.88, 0.91 for examiners 1, 2, and 3 respectively. Reliability coefficients for inter-examiners improved from 0.55 to 0.73 (Krippendorff alpha). The accuracy of identifying the diseased cases (high-grade dysplasia) increased from 0.82 to 0.94 (ROC curve). Binary logistic regression revealed that K19 positivity is negatively associated with hyperkeratinization of surface epithelium (P = 0.001). To conclude, for grading non-keratinized epithelial dysplastic lesions of the upper aerodigestive tract, paired K19-H&E stains proved to reduce inter and intra-examiner variability by highlighting the extension of dysplastic epithelial cells within epithelial thickness, thus identifying the involved epithelial third and assigning a more reliable and better reproducible grade.
上皮发育异常（ED）分级系统因可靠性低而受到批评。诊断测试或染色对上呼吸道消化道ED分级中减少检查者变异性的影响尚未得到研究。本研究的目的是检验细胞角蛋白19（K19）免疫染色在提高检查者之间和检查者内部ED分级可靠性方面的有效性，并再次强调K19阳性与上皮角化的关系。研究样本包括122个符合纳入标准的石蜡块。每个石蜡块切取三个切片：一个进行K19免疫染色，另外两个进行苏木精和伊红染色（H&E）。每位检查者对研究样本进行六轮分级；三轮仅使用H&E染色，三轮使用配对的K19-H&E染色。研究检查者为三名美国牙科委员会认证的执业口腔病理学家。使用Krippendorff's alpha、ROC曲线、卡方检验和二元逻辑回归分析结果。使用配对的K19-H&E染色后，结果显示，检查者1、2和3的分级检查者内部可靠性系数分别从0.70、0.69、0.78提高到0.73、0.88、0.91。检查者之间的可靠性系数从0.55提高到0.73（Krippendorff alpha）。识别患病病例（高级别发育异常）的准确性从0.82提高到0.94（ROC曲线）。二元逻辑回归显示，K19阳性与表面上皮过度角化呈负相关（P = 0.001）。总之，对于上呼吸道消化道非角化上皮发育异常病变的分级，配对的K19-H&E染色通过突出发育异常上皮细胞在上皮厚度内的延伸，证明可减少检查者之间和检查者内部的变异性，从而识别受累的上皮层并给出更可靠、可重复性更好的分级。
