Multinational study of oestrogen and progesterone receptor immunocytochemistry on breast carcinoma fine needle aspirates

?. P. Marin?ek, N. Nolde, I. Kardum‐Skelin, R. Nizzoli, B. Önal, T. Rezanko, E. Tani, K. T. Ostovi?, P. Vielh, F. Schmitt and G. Kocjan
Multinational study of oestrogen and progesterone receptor immunocytochemistry on breast carcinoma fine needle aspirates Objectives: To collect data on the variability of immunocytochemical (ICC) procedures used to detect oestrogen/progesterone receptors (ER/PR) on cytological material; to test the reproducibility of results; and to identify the crucial points in the ICC procedures that affect the result. Methods: Ten laboratories from eight countries participated in a two‐part study. In the first part, one of the participants (the coordinator) prepared and distributed cytospins from a fine needle aspirate of a primary breast carcinoma. Laboratories performed ICC staining for ER/PR according to their own methods on the test slides and in‐house positive controls. Slides were returned to the coordinator together with information on the preparation of positive control slides and the ICC methodology used. In the second part, obligatory methods of fixation and antigen retrieval were specified. Evaluation of results included grading the number of positive cells, staining intensity, background staining, cytoplasmic staining, sample condition and cellularity. Participants evaluated their own results, which were subsequently evaluated by the coordinator. Results: There was great variability in the preparation of slides for in‐house controls and ICC methodology. The outcome of ICC staining of in‐house control slides was excellent in two laboratories, adequate in three, sub‐optimal in four and inadequate in one. Only six obtained a positive reaction on the test slides and not all were of a high quality. Results of the second run were greatly improved in terms of cellularity of in‐house positive control slides, and scores for the percentage of stained cells and staining intensity of control and test slides. Cytospins and monolayer (ThinPrep^®) preparations were superior to direct smears; methods of fixation and antigen retrieval were the key points in the staining process. Conclusions: Our experience points to the need for guidelines for hormonal receptor determination and external quality control on cytological material, in order for cytological methods to be used in routine clinical practice with a suitable degree of confidence.     

Diagnostic efficacy of immunocytochemistry on fine needle aspiration biopsies processed by thin-layer cytology

OBJECTIVE: To evaluate the efficacy of immunocytochemistry (ICC) performed on smears processed by thin-layer cytology (TLC). STUDY DESIGN: During the period January 2001-September 2003, 3,573 consecutive fine needle aspiration biopsies were processed with both conventional smears (CSs) and TLC diagnosed by a single pathologist; 113 required immunocytochemical study. CSs were fixed in ethanol whereas TLC slides were processed with the ThinPrep 2000 method (Cytyc Co., Marlborough, Massachusetts, U.S.A); both were stained with Papanicolaou stain. ICC staining was carried out on only TLC slides. RESULTS: The 113 cytologic cases were grouped as follows: 32 thyroid nodules with 16 histologic controls (HCs), 24 lymph nodes (regardless of location) with 15 HCs, 18 liver and pancreatic lesions (3 HCs), 11 lung nodules (6 HCs), 5 kidney and adrenal gland lesions (1 HC), 6 abdominal (2 HCs) and 4 mediastinal masses (1 HC), 6 salivary gland tumors (3 HCs), 4 bone masses (2 HCs) and 3 subcutaneous lesions (1 HC). ICC contributed to the diagnosis in 104 cases (92%), whereas it was inconclusive in 9. The cytologic diagnoses were histologically confirmed in 46 of 50 cases (92%). CONCLUSION: ICC can be successfully applied on TLC slides with better results than on CSs, and its yield can be useful in making the correct diagnosis on fine needle aspiration biopsy.     

Control specimens for immunocytochemistry in liquid‐based cytology

T. Hansen, H. Pedersen, V. Brauner and J. Hariri Control specimens for immunocytochemistry in liquid‐based cytology Objective Immunostaining necessitates the use of positive as well as negative controls, which is usually an easy procedure in immunohistochemistry (IHC). To find suitable control specimens for immunocytochemistry (ICC) is, on the other hand, a challenging task and to the best of our knowledge is not sufficiently dealt with in the English literature. The aim of this trial was to develop an applicable method to select, collect, process and store control specimens for ICC using liquid‐based cytology (LBC). Methods The study included 21 different antibodies, which were known to react with at least one of the cellular components from tonsils, serous fluids and bronchial washings. The LBC specimens from the tonsils were collected as SurePath? specimens (BD, Bencton, Dickinson and Company) by brushing the cut‐surface of a fresh tonsil and then immersing the brush head into the SurePath? vial. The serous fluids and bronchial washings were fixed in CytoRich Red? (BD). Some of the cellular suspensions from the tonsils and equal amounts of the serous fluid and the bronchial washings were also mixed as a cocktail. Unstained SurePath slides were then prepared on the PrepStain? (BD) Non‐GYN Program, and the unstained and dry slides were then stored at 5 °C to test the effect of storage on the preservation of the antigenicity. ICC was then performed on BenchMark‐XT?. Results Cellular components in unstained SurePath? slides reacted positively with relevant antibodies. Slides that were stored for up to 40 days did not loose staining intensity. Conclusion Specimens from body fluids and cell‐suspensions that are collected by brushing the cut‐surface from different types of fresh tissues or organs can be used as control specimens either separately or as mixtures. Dry and unstained slides can then be prepared and stored in a refrigerator for at least 40 days without loosing staining intensity.     

Air-dried smears for optimal diagnostic immunocytochemistry

OBJECTIVE: To exploit formalin-postfixed, air-dried smears for diagnostic immunocytochemistry (ICC). STUDY DESIGN: A series of 144 cases of diagnostic fine needle cytology samples in which air-dried, supplementary smears were available was used to exploit postfixation in the process of antigenic stabilization and rescue for immunocytochemical staining. RESULTS: Postfixation with formalin and with a formalin/ethanol solution gave comparable results as far as recovery and immunocytochemical detection of most monoclonal and polyclonal antibodies. The visualization of the antibody reactions was often superior to that obtained with wet-fixed slides, probably due to the interaction of slow cell dehydration with their consequent optimal flattening observed with formalin postfixation after short rehydration in physiologic saline. CONCLUSION: Although wet fixation of cytopathologic slides in 95% ethanol represents a common standard for ICC, the usage of formalin-postfixed air-dried smears proved reliable and efficient for antigenic rescue and may enter routine usage in cytopathology laboratories. Moreover, in some instances, the visual evaluation of results was easier in the larger, well-flattened cells obtained in air-dried cells.     

European guidelines for quality assurance in cervical cancer screening: recommendations for cytology laboratories.

The quality of a cervical cytology laboratory depends on adequate handling and staining of the samples, screening and interpretation of the slides and reporting of the results. These guidelines give an overview of procedures recommended in Europe to manage the balance between best patient care possible, laboratory quality assurance and cost effectiveness and will be published as a chapter 4 in the European Guidelines for Quality Assurance in Cervical Cancer Screening. The laboratory guidelines include protocols for personnel and organisation, material requirements, handling and analysing cervical samples, recording of results, quality management and communication. The section on quality management is comprehensive and includes protocols for all aspects of internal and external quality assurance. The guidelines are extensively referenced and as far as possible the recommendations are evidence-based.     

Desmin detection in FNAB samples of rhabdomyosarcoma: an immunocytochemical study

We performed immunocytochemical (ICC) staining for desmin on 65 fine needle aspiration biopsies from 45 patients with rhabdomyosarcoma, using the avidin-biotin-peroxidase complex method (ABC), and two types of antibodies, D33 and DE-R-11. The material was fixed either in ether-alcohol or in Delaunay's solution. The ABC method was applied to Papanicolaou stained slides, without destaining. We compared the quality of staining on fresh, routinely prepared slides vs archival material and the quality of staining on smears vs cytospins. In 20 cases, D33 and DE-R-II were applied to a pair of slides from the same tumour sample in order to see if there was any difference in their ability to recognize desmin. Desmin was positive in all 18 cases in which ICC staining was performed at the same time diagnoses were given. Among the 27 cases where ICC staining was carried out on archival material, seven were negative. Slides from four of these cases were 20 or more years old and negative reaction could be attributed to heating of slides before coversliping and/or to uneven distribution of desmin immunoreactivity in tumours. The second reason was probably the cause of negative reactions in cases from 1985 and 87. The type of slide preparation had no influence on the quality of staining. However, results were easier to read on cytospins because cells were more evenly distributed. Finally, our results proved that there was no significant difference between D33 and DE-R-11 in their ability to recognize desmin.     

Immunocytochemistry on scrape cytology in breast cancer: will it unearth the weaker positives?

OBJECTIVE: To standardize the technique of immunocytochemical (ICC) assessment of estrogen (ER) and progesterone receptor (PR) status in breast cancer by scrape cytology and to compare the results with immunohistochemistry on paraffin blocks. STUDY DESIGN: ICC assessment for ER and PR was done on scrape smears from tissue samples in 200 cases of primary breast cancer. The results were compared to those obtained from immunohistochemical (IHC) evaluation of formalin-fixed paraffin same tissue samples. RESULTS: ER/PR positivity rates as well as staining scores were compared between the scrape smears and tissue sections. The concordance between cytology and histology was 84% for ER and 90% for PR. Both the positivity rates and the staining intensity scores were higher for cytochemistry than for histochemistry. CONCLUSION: The ICC method on scrape smears is a simple test with rapid turnaround time. The sample required is small, and antigen loss due to fixation and processing is minimal. This new method gives a higher yield of hormone receptor positivity and, when used in conjunction with the IHC method, may improve the pickup rate of ER-positive cases, thereby playing an important role in risk stratification and therapeutic decision making in patients with breast cancer.     

Immunocytochemical staining of effusions; an external quality control study in The Netherlands

Immunocytochemical staining of effusions; an external quality control study in The Netherlands
In The Netherlands an external quality control study of immunocytochemical (IC) staining of effusions was initiated, consisting of three test rounds. The 12 participating laboratories received samples of malignant effusions (runs 1, 2 and 3), and five unstained control specimens prepared from the same material in runs 2 and 3. The laboratories used their own protocols to prepare and stain the samples ('in‐house' specimens). Two persons viewed and scored the slides following preset criteria concerning number and morphology of diagnostic cells, background staining and staining specificity. Better scoring results were found for control specimens, compared with 'in‐house' specimens, primarily caused by cell loss in the latter. This finding underlines the view that high quality IC needs well organized processing and staining procedures, and warrants external quality control systems.     

EMMPRIN (CD147) expression and differentiation of papillary thyroid carcinoma: implications for immunocytochemistry in FNA cytology

Y. Aratake, K. Marutsuka, K. Kiyoyama, T. Kuribayashi, T. Miyamoto, K. Yakushiji, S. Ohno, Y. Miyake, T. Sakaguchi, T. K. Kobayashi, A. Okayama, K. Tamura and E. Ohno
EMMPRIN (CD147) expression and differentiation of papillary thyroid carcinoma: implications for immunocytochemistry in FNA cytology Objective: Extracellular matrix metalloproteinase inducer (EMMPRIN) and its induced matrix metalloproteinases (MMPs) play a crucial role in tumour progression, invasion and metastasis. EMMPRIN expression has been demonstrated in several tumours, but its expression profile in thyroid cancer remains unclear. Methods: We evaluated the expression profile of EMMPRIN at various stages of differentiation of thyroid carcinoma, including 20 cases of well‐differentiated papillary carcinoma (WDPC), 15 cases of papillary carcinoma with a poorly differentiated carcinoma component (PC/PDC) and four cases with an undifferentiated carcinoma (UDC) component, using paraffin‐embedded sections for immunohistochemical stains. Also, we used 32 fine needle aspiration cytology and imprint smears from the same cases for immunocytochemical stains. The staining results were evaluated with a scoring system. Results: Immunohistochemical staining showed that EMMPRIN expression was absent or weak in almost all WDPC specimens, whereas it was moderate or strong in PDC and UDC components. In tumours that showed a gradual morphological transformation from WDPC to PDC components, the expression of EMMPRIN was progressively stronger from the areas of WDPC to those of PDC. WDPC, PC/PDC and UDC had expression scores of 4.9, 45.0 and 245.7, respectively. Results of immunocytochemical staining showed almost the same staining profile as those of immunohistochemical staining. The cytological atypia of EMMPRIN‐positive cells was greater than that of negative cells. Conclusion: These results indicated that EMMPRIN expression correlates significantly with the degree of dedifferentiation of thyroid carcinoma. This study demonstrates the feasibility of expression of EMMPRIN using fine needle aspiration samples. Therefore, immunocytochemical analysis of EMMPRIN may be a novel aid to evaluate the differentiation of thyroid carcinoma.     

Oral exfoliative cytology in the diagnosis of paracoccidioidomycosis

OBJECTIVE: To assess the efficacy of conventional oral exfoliative cytology as a diagnostic tool in paracoccidioidomycosis. STUDY DESIGN: Cytologic smears and incisional biopsies were obtained from 10 patients with a clinical suspicion and oral manifestations of paracoccidioidomycosis. Cytologic smears and sections of the incisional biopsy underwent methenamine silver staining for fungi according to the Gomori-Grocott method. The dry glass slides were examined at 400 or 1,000 x magnification, and the presence and shape of yeasts of Paracoccidioides brasiliensis were investigated. RESULTS: Yeasts of the fungus P brasiliensis were clearly identified in cytologic smears and sections from incisional biopsies in all cases analyzed (100.0%). CONCLUSION: Cytology of oral samples proved an effective diagnostic method for the detection of paracoccidioidomycosis in humans.     

Use of the ThinPrep Imaging System for internal quality control of cervical cytology

T. Heard, A. Chandra, G. Culora, S.S. Gupta, A. Herbert and M. Morgan
Use of the ThinPrep Imaging System for internal quality control of cervical cytology Objective: To audit the use of the ThinPrep Imaging System (TIS) for internal quality control (IQC) in the place of rapid review (RR), and to compare its performance with routine primary screening. Method: During 9 months, 16 462 ThinPrep slides were processed by TIS. Slides were initially reviewed using the TIS review scope, as recommended by the manufacturer: 22 fields of view were observed and, if considered abnormal, a full microscopic review was conducted using the review scope. Different biomedical scientists (BMSs), working on each procedure in rotation, performed batches of TIS‐assisted quality control and routine primary screening independently on unmarked slides. Any slides with abnormalities detected by either method were referred to a consultant pathologist or advanced BMS practitioner for a final report. TIS results were compared with both previous records of RR and routine primary screening carried out on the same slides. We used the UK terminology in which ‘dyskaryosis’ is equivalent to squamous intraepithelial lesion (SIL) and borderline to atypical (including squamous and glandular cells). Results: TIS preview detected significantly more high‐grade dyskaryosis compared with RR during the previous 4 years: 2.0–4.2 compared with 0.1–1.8 detected per 1000 slides (P = 0.0001). TIS and routine screening were equivalent in sensitivity and specificity for the final cytology result, but BMSs were significantly more likely to classify slides as dyskaryotic rather than borderline when using TIS compared with routine screening. Referrals for potentially high‐grade abnormalities detected by TIS‐assisted IQC alone found 28 biopsies of at least cervical intraepithelial neoplasia grade 2 (CIN2+), whereas 15 CIN2+ biopsies were found on routine screening but missed using TIS. There was no significant change in the rates of inadequate tests, high‐ or low‐grade cytological abnormalities, or positive predictive value for CIN2+ when TIS was in use. Conclusions: Screening with TIS was more sensitive than RR for IQC, providing a rescreening method equivalent to routine primary screening in overall accuracy.     

Quality control in cervicovaginal cytology by cytohistological correlation

N. Izadi‐Mood, S. Sarmadi and S. Sanii
Quality control in cervicovaginal cytology by cytohistological correlation Objective: Frequent studies attest to the correlation of cytological interpretations with defined histopathological entities. Nevertheless, as part of quality control, cytology laboratories are required to compare Papanicolaou smear reports with those of cervical biopsies to search for discrepancies. We have attempted to determine and categorize the causes of existing discrepancies in our laboratory in order to clarify the source of errors. Methods: We reviewed 670 cervical smears that were paired with subsequent punch biopsy or endocervical curettage samples, obtained within 2 months of the cytology, and found out that 60 smear‐biopsy pairs were discrepant regarding the diagnosis. These cases were categorized into four error groups after careful re‐evaluation of the original smear and biopsy slides. Results: In 51 (85%) of 60 cervical smear‐biopsy pairs with reports that disagreed, the initial diagnoses of both cervical smear and biopsy were confirmed by the review opinion; in these cases, cytology and biopsy ‘sampling errors’ were responsible for 40 and 11 instances of discrepancy, respectively. Seven cases (11.1%) were discrepant due to ‘smear interpretation errors’ and consisted of five cases with initial under‐diagnosis and two cases with initial over‐diagnosis. One case (1.7%) was due to ‘screener error’. In another case, discordance was due to cervical ‘biopsy interpretation error’, with initial over‐diagnosis as squamous intraepithelial lesion. Conclusion: In this retrospective study, we determined the causes of cytohistological discrepancies in cervical samples. The main explanation for discrepancy was ‘sampling error’.     

Intraoperative evaluation of sentinel lymph nodes in breast cancer: comparison of frozen sections,imprint cytology and immunocytochemistry

M. Francz, K. Egervari and Z. Szollosi
Intraoperative evaluation of sentinel lymph nodes in breast cancer: comparison of frozen sections, imprint cytology and immunocytochemistry Objective: We analysed the utility of imprint cytology with rapid immunocytochemistry and frozen section analysis for the evaluation of sentinel lymph nodes in breast cancer patients. Methods: The sensitivity, specificity, and positive and negative predictive values have been calculated for each method individually, each pair and all three together. We compared these results with those of routinely processed paraffin sections. Results: The sensitivity and specificity of each of the three methods for detection of metastatic carcinoma were as follows: 69.4% and 97.8% for touch imprint cytology; 58.3% and 100% for frozen sections; 68.5% and 98.9% for rapid immunocytochemistry. When the methods were combined, the highest accuracy was achieved by touch imprint cytology, frozen sections, touch imprint cytology plus rapid immunocytochemistry, or touch imprint cytology frozen section analysis and rapid immunocytochemistry, each of these having identical sensitivity and specificity of 72.2% and 97.8%, respectively. Conclusions: In our study the combined accuracy of the three methods was the same as combining touch imprint cytology and frozen sections or touch imprint cytology plus rapid immunocytochemistry. Rapid immunocytochemistry provides an additional parameter and preserves tissue for permanent sections.     

External quality assessment in gynaecological cytology: The Trent Region experience

A Department of Health Executive Letter stated in 1998 that the principal function of external quality assessment (EQA) is educational. Subsequently, in England, it has no longer been acceptable to assess performance in gynaecological cytology by proficiency testing. This paper describes the EQA scheme in gynaecological cytology that has been run by the Trent Regional Gynaecological Pathology Quality Assurance Group for the NHS Cervical Screening Programme (NHSCSP) since 1998. It conforms as closely as possible to the recommendations published by the Department of Health Working Group on Histopathology EQA Accreditation, and replaced the national proficiency testing protocol. The educational value of the scheme is derived predominantly from a numerical score which provides confidential and quantitative feedback to all participants. Personal performance monitoring occurs as a secondary function. For primary screeners and checkers, this is based purely on the distinction between negative, inadequate and abnormal smears. For pathologists, personal performance monitoring also includes grading of abnormalities. The EQA has been designed so that all professional groups participate in a manner that closely mimics normal practice. Only slides that have achieved an 80% consensus amongst participants are used in the EQA. Substandard performance has been defined as those participants with scores falling below the 2.5%ile. The paper describes the EQA in detail and illustrates its use by means of the second round results. The EQA protocol developed within Trent and described in this paper has contributed to proposals contained in the current national EQA in gynaecological cytology for the NHSCSP. In particular this paper highlights the effectiveness of the scoring system contained within the Trent and National EQA protocols.     

Development of a technical external quality assurance scheme in non‐gynaecological cytology in UK

Technical external quality assurance (EQA) schemes are well established for histopathology and cervical cytology but, to date, sadly lacking for diagnostic cytology (DC). This timely review redresses the balance by describing the development and evaluation of a technical EQA scheme for DC available to the UK, Europe and beyond.     

Detection of bladder cancer by multitarget multicolour FISH: comparative analysis on archival cytology and paraffin-embedded tissue

Detection of bladder cancer by multitarget multicolour FISH: comparative analysis on archival cytology and paraffin-embedded tissue We have evaluated the possibility of using the same specimen for both cytological diagnosis and multitarget multicolour FISH (MtMcFISH) analysis in order to determine whether the routinely processed specimens used for diagnosis were also suitable for this ancillary procedure. For this purpose 18 positive samples (11 voided urine and seven bladder washings) were selected, together with a representative section of the corresponding immediately previous or subsequent histological specimens. Two negative cytology slides were added as negative controls. FISH analysis revealed a normal pattern for each probe in the two negative controls and an abnormal pattern in the 18 positive cases. In the latter the same FISH alterations were found in the cytology samples and in the corresponding histological sections, and superimposable cytological/histological features were observed in two cases where two different histology samples were analyzed. The results clearly show that MtMcFISH may be successfully applied to destained routinely processed cytology slides.     

Immunocytochemical detection of Ki‐67 in Diff‐Quik‐stained cytological smears of canine mammary gland tumours

U.S. Choi and D.Y. Kim Immunocytochemical detection of Ki‐67 in Diff‐Quik‐stained cytological smears of canine mammary gland tumours Objective: To investigate whether Diff‐Quik stained fine needle aspirate smears can be used to evaluate Ki‐67 expression by immunocytochemistry. Methods: Both cytological and histological samples were obtained from 24 dogs with spontaneously developed mammary gland tumours. The cytological and histological specimens were examined by Diff‐Quik and H&E stains, respectively. After examination, both samples were immunostained using the same Ki‐67 antibody. The % Ki‐67 values were calculated based on the percentage of positively stained tumour cells per 500 and 1000 tumour cells in cytology and histology specimens, respectively. Results: Ki‐67 staining was successful in 17/24 smears (71%) and 19/23 sections (83%). The correlation coefficient between the percentage of Ki‐67‐positive cells in cytological smears and in the histological sections was 0.677 (P < 0.01). These values were significantly different between histologically benign and malignant tumour groups both in cytology and histology samples (P < 0.001). The threshold value of the percentage of Ki‐67‐positive cells for distinguishing benign from malignant tumours was set at 4.85% with 90.9% sensitivity and 92.3% specificity by Receiver Operating Characteristic (ROC) curve using histopathology as the gold standard. Conclusion: Diff‐Quik‐stained cytology smears can be used to detect the presence of Ki‐67 antigen when histology sections are not available.     

BSCC Code of Practice – fine needle aspiration cytology

The British Society for Clinical Cytology Code of Practice on fine needle aspiration cytology complements that on exfoliative cytopathology, which was published in the last issue ( Cytopathology 2009; 20 :211–23). Both have been prepared with wide consultation within and outside the BSCC and have been endorsed by the Royal College of Pathologists. A separate code of practice for gynaecological cytopathology is in preparation. Fine needle aspiration (FNA) cytology is an accepted first line investigation for mass lesions, which may be targeted by palpation or a variety of imaging methods. Although FNA cytology has been shown to be a cost-effective, reliable technique its accurate interpretation depends on obtaining adequately cellular samples prepared to a high standard. Its accuracy and cost-effectiveness can be seriously compromised by inadequate samples. Although cytopathologists, radiologists, nurses or clinicians may take FNAs, they must be adequately trained, experienced and subject to regular audit. The best results are obtained when a pathologist or an experienced and trained biomedical scientist (cytotechnologist) provides immediate on-site assessment of sample adequacy whether or not the FNA requires image-guidance. This COP provides evidence-based recommendations for setting up FNA services, managing the patients, taking the samples, preparing the slides, collecting material for ancillary tests, providing rapid on-site assessment, classifying the diagnosis and providing a final report. Costs, cost-effectiveness and rare complications are taken into account as well as the time and resources required for quality control, audit and correlation of cytology with histology and outcome. Laboratories are expected to have an effective quality management system conforming to the requirements of a recognised accreditation scheme such as Clinical Pathology Accreditation (UK) Ltd.     

The big problem of the missing cytology slides

Cytology slides are often unique and irreplaceable. Unlike surgical pathology cases, where additional paraffin sections can be cut, cytology slides often cannot be duplicated because there are only a few direct smears or the diagnostic material is present on a single slide. Cytology slides are often "sent out" to other physicians, laboratories or hospitals, typically so that the pathologist at the institution where the patient will receive treatment can review the slides. Less often, a cytology lab sends out the slides for a second opinion or as part of the discovery process in a lawsuit, where they may or may not be defendants. Rarely, unique and irreplaceable cytology slides are lost. This article presents a hypothetical scenario that is based on reported state appellate court decisions. The article discusses some of the legal issues that will affect the defendant cytologist/cytology lab and the "expert cytologist," and suggests some steps a cytologist/cytology lab can take to minimize the risk of repercussions from a lost unique and irreplaceable cytology slide.     

Critical role of fine needle aspiration cytology and immunocytochemistry in preoperative diagnosis of pediatric renal tumors

OBJECTIVE: To evaluate accuracy and role of immunocytochemistry (ICC) in cytologic diagnosis of pediatric renal tumors. STUDY DESIGN: Fine needle aspirates from 75 cases of pediatric renal tumors were studied. Radiologic-guided aspirations were performed, with 6-7 smears stained with Papanicolaou and Giemsa stains. Smears were screened without the knowledge of final histologic diagnosis. Subsequently, clinical details, final histology and diagnosis rendered by the original cytologist were noted to judge accuracy of diagnosis by a sensitized cytologist. Five neuroblastomas that entered close differentials for Wilms tumor were also evaluated. ICC studies were also performed after staining. RESULTS: Of 58 Wilms tumors, 5 were misdiagnosed; 3 renal rhabdoid tumors and 1 clear cell sarcoma were missed on cytology. Non-Hodgkin's lymphomas presenting as renal masses were accurately diagnosed on cytology, but primitive neuroectodermal tumors (n = 3) and renal cell carcinomas (n = 2) were not accurately diagnosed. Accuracy rate improved from 65% to 92% on review by a cytologist aware of cytologic features of pediatric renal tumors. CONCLUSION: A good accuracy rate of diagnosis of pediatric renal tumors can be achieved by priming pathologists to typical features of tumors. Immunocytochemistry plays a supportive role in cases with atypical morphology or unusual presentations.