CD79a (Fig. 2) Among 112 laboratories submitting stains in the latest run, most used mAb clone JCB117 and obtained sufficient results in 85%. In contrast, all of the six laboratories using mAb clone HM57 obtained poor marks, due to insufficient staining of neoplasms (Fig. 2) Even the Dako Web site suggests that the clone JCB117 be preferred over HM57 but the datasheet does not outline the problems with the use , of clone HM57 on human material*. Cytokeratins, low molecular weight (CK-LMW) (Fig. 3) Looking at 5 mAb clones used by at least six laboratories in the latest runs, the proportion of sufficient stains was: 35betaH11: 6/26 (23%), 5D3: 9/15 (60%), C51: 13/14 (93%), CAM 5.2: 21/47 (45%), and DC10: 33/37 (89%). The prevalent feature of an insufficient staining was a very weak or false - negative staining of liver cells or cells of the renal cell carcinoma (Fig. 3). Virtually all the laboratories were able to detect CK-LMW in columnar epithelial cells, emphasizing that these cells cannot be used as CSQI. While suboptimal results were in part due to insufficient or inappropriate epitope demasking, it was also confirmed by retesting in the NordiQC laboratory that differences in the performance of the antibodies was an important parameter (Fig. 3). Consequently, a change in clone was recommended to laboratories using one of the less successful clones Discussion For the majority of the IHC tests, optimal staining results can be obtained by following different protocols for antigen retrieval techniques, primary antibodies or visualization systems. Although individual choices of protocols are necessary for new developments of reagents, systems and instruments, these procedures complicate the approach to standardization. It is in this context that the identification of tissues containing CSQI becomes important. Unfortunately, neither the scientific literature nor the vendors datasheets are focused on this issue. NordiQC puts special emphasis on the identification of robust control tissues enabling the laboratories to reliably validate their own staining results. It also encourages the laboratories to join the efforts of standardization. NordiQC is careful to advice laboratories how to improve their performance based on readily accessible solutions. Basically, improvement of the protocols can be readily done by the participating laboratory that uses so-called open staining systems when the analytical problems are identi, fied and the laboratory has become aware of the CSQI. However, when insufficiencies are detected in so-called closed staining systems there , is very little that the participating laboratory can do, and the producers of such closed systems and RTU products should change test parameters. With regard to proper HIER, the advantage of the alkaline buffers in terms of enhanced sensitivity and analytical robustness has been confirmed in the NordiQC reference laboratories for almost all the markers tested. When an efficient HIER is applied, endogenous biotin is also revealed (8) inevitably giving false-positive staining reactions in many tissues and tumors in biotin-based detection systems. The best solution to overcome this problem is to implement a non-biotin based visualization system. NordiQC is cautious in suggesting change of antibody unless the evidence that this should be done is strong. In some cases, tests in the NordiQC reference laboratory sustain the suspicion obtained from the results of many participating laboratories that an optimal staining with a certain primary antibody is difficult or impossible, as is the case with several cyclin D1 antibodies (9) and cytokeratin antibodies as illustrated in this paper. When confirmatory tests have not been carried out, it cannot be excluded that an unsuccessful antibody would eventually produce optimal results by adjustments of the protocols. In calibration of the dilution of the concentrated primary antibodies, the CSQI in the control tissues will determine the optimal dilution. Such indicators should enable laboratories to adjust the concentrations of the primary antibodies to produce the required staining results irrespective of their protocol platform. In contrast, RTU antibodies (pre-diluted antibodies), which have not been properly developed to meet the present diagnostic criteria or to fit into various protocol settings, often result in insufficient stains**. NordiQC has demonstrated that significant improvement may be achieved as a direct consequence of EQA that provides feedback to the less successful laboratories with an explanation of the probable cause of the insufficiency and individually-adjusted recommendations for protocol improvement. The strong correlation between protocol adjustments (according to NordiQC advice) and improved laboratory performance is even more encouraging as it directly reflects the benefit of quality assurance Conclusion EQA should be implemented in all IHC laboratories in the healthcare system as well as in any company guided by the same goals and principles that apply to other clinical laboratory testing. While standardization of methods does not appear possible, the emphasis should be focused on standardization of controls and staining results. It has to be taken into account that such standards are not invariable, but must be adjusted in parallel with the development of knowledge as well as future technical developments. Consequently, EQA organizations that continuously survey IHC performance in the pathology laboratories must be accessible and considered to be obligatory for diagnostic anatomic pathology. *Since the editing of this article, Dako has made the necessary changes to correct this information in production lot of the CD79, clone HM57 antibody. **A new pathology quality endorsed RTU product line will be launched by Dako in March 2008 47 | Connection 2008
April 2008, VOL 11 Connection IHC STANDARDIZATION AROUND THE WORLD In this issue Q&A with Patho
Contents APRIL 2008, VOL 11 2 3 4 Editorial George L. Kumar, PhD Featured Laboratory The Osamura
Editorial Immunohistochemistry (IHC) Standardization Around the World George L. Kumar, PhD Managing
Featured Laboratory The Osamura Laboratory Laboratory headed by Prof. Robert Yoshiyuki Osamura, MD,
Q&A Ask the Experts: On Immunohistochemistry (IHC) Standardization Professor Leong is Medical Di
time interval between removal of tissue and immersion in fixative, the temperature of tissue storage
Connection: How would you like to standardize IHC in Australia? As discussed above, standardization
Connection: Antigen retrieval is essential in immunohistochemistry (IHC) in order to restore epitope
Connection: Is a universal image analysis system feasible? No, not until we standardize the all impo
Q&A Fernando Soares, MD, PhD University of São Paulo, São Paulo, Brazil Dr. Fernando Soares is F
Connection: In your opinion, what is the biggest hurdle for standardization? Probably education in l
There are no standards in Latin America. We always follow the manufacturers protocol during our firs
Q&A Bryan R. Hewlett, ART, MLT Consultant Technologist to the Anatomic Pathology EQA program of
There is no standardization of AR steps circumstances, it would be impossible toand, undera the pre
Connection: How would you rate European (UK NEQAS, NordiQC) and US IHC standards to Canadian IHC sta
Q&A Prof. Chen Jie Prof. Cui Quancai Peking Union Mediacl College Hospital, Beijing, China Prof.
Connection: According to Goldstein et al. Appl Immunohistochem Mol Morphol 2007;15:124133 Immunohis
Connection: Is it true that a particular histology feature may be better demonstrated by other fixat
Connection: What constitutes standardization of image analysis as applied to immunohistochemistry (I
Q&A Dr. Tanuja Manjanath Shet Dr. Vani Parmar Tata Memorial Hospital, Mumbai, India Tanuja Manj
... the biggest hurdle in India is suboptimal fixation and processing of tissues. Though I agree th
Connection: Is it true that a particular histology feature may be better demonstrated by other fixat
Connection: Can you comment on the internal and external quality control (EQC) procedures followed i
Q&A Prof. Robert Yoshiyuki Osamura Department of Pathology, Tokai University School of Medicine
Connection: In your opinion, what is the biggest hurdle for standardization? The biggest hurdle for
the standardization of image ... appropriate for pre-screeninganalysis is of the staining quality.
Connection: Why is standardization of image analysis in diagnostic pathology important? Because the
Q&A James F. Happel, DLM (ASCP), HTL Technical Director of Surgical Pathology, Research and Deve
Connection: United Kingdom National External Quality Assessment Service (UK NEQAS) helps to ensure t
Connection: The American Society of Clinical Oncology (ASCO) and the College of American Pathologist
would recommend that standardization Ibegin with identifying a reliable and trustworthy source ...
Interview Immunohistochemistry for Oestrogen and Progesterone Receptors Dr. Andrew Lee Consultant H
Connection: What is the difference between the H score and the Allred score? Which is better? What d
Connection: Can you comment on the burden in the laboratory, if one changes from a current ER/PR ass
Opinion & Interview IHC Standardization: A Dako Perspective Dr. Ole Rasmussen R&D Director,
Connection: Dako has developed Readyto-Use Antibodies for in vitro diagnostic applications. How is t
Articles UK NEQAS-ICC & ISH: Historical perspective, current role, future directions Andy Dodso
UK NEQAS-ICC in the 1990s In his first year as Scheme Organiser, Keith oversaw the transition to sub
The application could be argued to represent a field change in terms of the rigour with which the an
Assessment teams consist of four assessors, who view slides around a multi-headed microscope and sco
The archive which UK NEQAS holds, both in terms of stained slides and methodological data, must sure
For Immunocytochemistry and FISH RESULT: RUN 80L SLIDE: NEQAS Laboratory No: XXX Mr. A. Scientist De
Figure 6. Feedback on results has always been given high priority, and for many years this has been
a b c d Figure 7. The antigen chosen by Gerry Reynolds for his very first assessment run was kap
Bibliography Selected UK NEQAS-ICC & ISH papers. Ibrahim M, Dodson AR, Barnett S, Fish D, Jasani
Articles Nordic Immunohistochemical Quality Control (NordiQC) An Organization for External Quality A
parameters (i.e. results interpretation and reporting) (4, 5). In an EQA setting, by circulating ser
CD79a (Fig. 2) Among 112 laboratories submitting stains in the latest run, most used mAb clone JCB11
References 1. Rhodes A, Jasani B, Barnes DM, Bobrow LG, Miller KD. Reliability of immuno-histochemic
Fig. 2. CD79a A. Optimal CD79a staining of the tonsil using the monoclonal antibody (mAb) clone JCB
Standardization of Ki-67 Immunohistochemical Staining for Diagnosing Grade of Gastrointestinal Strom
was conducted in 49 GIST cases. The concordance rate for the evaluation results at three laboratorie
CB pH6 a b c d TE pH9 e f g h Autoclave 121° C/10 min Water bath 95° C/40 min Microwave
50 Table 1. Correlation between NCC and STD methods R2=0.9483 Categories of proportion NCC Method 3
Opinions Importance of Standardization for Predictive Prognosis David J. Dabbs, MD Chief of Pathol
is documented and serves as a surrogate marker for the initial exposure to formalin. Since the first
Opinions The New Era for ER and PRIts time to Standardize! Dr. Ian Ellis, B.Med.Sci. BM, MS, FRCpa
et al 2001). The main reason for false-negative results is due to inefficient heat-induced epitope (
Standardization of HER2 TestingInconsistency Raises Questions Opinions Sunil S. Badve, MD, FRCPath
rence seen in these trials is in the order of 50%. This is the major reason for all the excitement a
which now requires expression of HER2 by at least 30% of tumor cells (instead of 10%). It has also r
IHC CONSENSUS MEETING, JANUARY 27 2008, SANTA BARBARA, CA, USA , IHC CONSENSUS MEETING, JANUARY 27,
Richard Cartun, PhD, Sunil Badve, MD Jon Askaa, PhD Søren Nielsen, HT, CT, Mogens Vyberg, MD Elizab
Dako Abstracts Abstracts presented at the 30th Annual San Antonio Breast Cancer Symposium December
Dako Abstracts Amplification of ESR1 may predict resistance to adjuvant tamoxifen in postmenopausal
Dako Abstracts Abstracts presented at the United States and Canadian Academy of Pathology (USCAP) A
Dako Abstracts Metastatic Pancreatic Endocrine Tumors in the Liver Express KOC Briones AJ, Bourne P
Dako Abstracts Merkel Cell Carcinomas Express K Homology Domain Containing Protein Overexpressed in
Dako Abstracts Immunohistochemical Analysis of KOC/IMP3 in Malignant Pleural Mesothelioma Xu H, Sim
Dako Abstracts KOC, TTF-1 and CDX2 Discriminate Small-Cell Carcinoma from Carcinoid and Pancreatic
Dako Publications Publications Co-authored by Dako: In Press Li L, Xu H, Spaulding B, Cheng L, Si
Dako Meetings 2007 - National Society for Histotechnology Meeting. Denver, CO NSH workshop attend
New Premium Quality Concentrated Antibodies New Products Your current and future needs drive the c
Targeting Colorectal Adenocarcinomas, Anti-TIMP-1 and Anti-Villin Monoclonal Mouse Anti-Human Tissue
Dakos FLEX Ready-to-Use Concept Enhance performance of your laboratory by running FLEX Ready-to-Use
2008 Product Catalog Available Now! The catalog features more than 170 new products, including the A