Maxwell P, McCluggage W G
Quantitative Biomarkers Group, Cancer Research Centre, Queens University of Belfast and Institute of Pathology, Royal Group of Hospitals Trust, Belfast BT12 6BA, Northern Ireland, UK.
J Clin Pathol. 2000 Dec;53(12):929-32. doi: 10.1136/jcp.53.12.929.
Although positive and negative controls are performed and checked in surgical pathology cases undergoing immunohistochemistry, internal quality control procedures for immunohistochemistry are not well described. This study, comprising a retrospective audit, aims to describe a method of internal quality control for immunohistochemistry. A scoring system that allows comparison between cases is described.
Two positive tissue controls for each month over a three year period (1996-1998) of the 10 antibodies used most frequently were evaluated. All test cases undergoing immunohistochemistry in the months of April in this three year period were also studied. When the test case was completely negative for a given antibody, the corresponding positive tissue control from that day was examined. A marking system was devised whereby each immunohistochemical slide was assessed out of a possible score of 8 to take account of staining intensity, uniformity, specificity, background, and counterstaining. Using this scoring system, cases were classified as showing optimal (7-8), borderline (5-6), or unacceptable (0-4) staining.
Most positive tissue controls showed either optimal or borderline staining with the exception of neurone specific enolase (NSE), where most slides were unacceptable or borderline as a result of a combination of low intensity, poor specificity, and excessive background staining. All test cases showed either optimal or borderline staining with the exception of a single case stained for NSE, which was unacceptable.
This retrospective audit shows that immunohistochemically stained slides can be assessed using this scoring system. With most antibodies, acceptable staining was achieved in most cases. However, there were problems with staining for NSE, which needs to be reviewed. Laboratories should use a system such as this to evaluate which antibodies regularly result in poor staining so that they can be excluded from panels. Routine evaluation of immunohistochemical staining should become part of everyday internal quality control procedures.
尽管在接受免疫组织化学检查的外科病理病例中会进行阳性和阴性对照并加以检查，但免疫组织化学的内部质量控制程序却没有得到很好的描述。本研究通过回顾性审核，旨在描述一种免疫组织化学内部质量控制方法。文中描述了一种能对病例进行比较的评分系统。
对三年期间（1996 - 1998年）最常用的10种抗体，每月的两种阳性组织对照进行评估。还研究了这三年期间4月接受免疫组织化学检查的所有测试病例。当测试病例对某一特定抗体完全呈阴性时，检查当天相应的阳性组织对照。设计了一种评分系统，根据染色强度、均匀性、特异性、背景和复染情况，对每张免疫组织化学切片进行0至8分的评分。利用该评分系统，将病例分为染色最佳（7 - 8分）、临界（5 - 6分）或不可接受（0 - 4分）三类。
除神经元特异性烯醇化酶（NSE）外，大多数阳性组织对照显示染色最佳或临界，由于强度低、特异性差和背景染色过多等综合因素，NSE的大多数切片不可接受或处于临界状态。除了一例NSE染色的测试病例不可接受外，所有测试病例均显示染色最佳或临界。
这项回顾性审核表明，可使用该评分系统对免疫组织化学染色切片进行评估。对于大多数抗体，大多数病例能实现可接受的染色。然而，NSE染色存在问题，需要重新审视。实验室应使用这样的系统来评估哪些抗体经常导致染色不佳，以便将其从检测组合中排除。免疫组织化学染色的常规评估应成为日常内部质量控制程序的一部分。
