The role of ThinPrep cytology in the evaluation of estrogen and progesterone receptor content of breast tumors

Breast fine-needle aspiration cytology in the era of core-needle biopsy: what is its role?

Fine-needle aspiration cytology (FNAC) has long been recognized as a minimally invasive, cost-effective, and reliable diagnostic tool for breast lesions. However, with the advent of core-needle biopsy (CNB), the role of FNAC has diminished in some clinical settings. This review aims to re-evaluate the diagnostic value of FNAC in the current era, focusing on its complementary use alongside CNB, the adoption of new approaches such as the International Academy of Cytology Yokohama System, and the implementation of rapid on-site evaluation to reduce inadequate sample rates. Advances in liquid-based cytology, receptor expression testing, molecular diagnostics, and artificial intelligence are discussed, highlighting their potential to enhance the diagnostic accuracy of FNAC. Despite challenges, FNAC remains a valuable diagnostic method, particularly in low-resource settings and specific clinical scenarios, and its role continues to evolve with technology.

The Evolving Role of Vacuum Assisted Biopsy of the Breast: A Progression from Fine-Needle Aspiration Biopsy

BACKGROUND

The management of breast disease has been greatly facilitated by the technology of needle biopsy interventions, and over the past 30 years, this has evolved from the use of fine-needle aspiration biopsy (FNAB) to the current methodology of vacuum assisted biopsy (VAB).

METHODS

This article provides an historical review of the application of needle interventions of the breast in the diagnosis and management of breast conditions, and discusses current indications for the use of vacuum assisted biopsies and vacuum assisted excisions.

RESULTS

Whilst FNAB continues to have a limited role in breast disease diagnosis, the necessity of achieving an histological diagnosis has preferentially seen the development and wider application of automated core needle biopsies (CNB) and VAB in the assessment and management of breast lesions. The advantages of CNB and VAB include the ability to distinguish in situ and invasive disease pre-operatively, and the ability to achieve prior knowledge of immunohistochemical tumour markers particularly in the setting of neoadjuvant drug treatments.

CONCLUSION

Due to its ability to obtain larger tissue samples, VAB does have diagnostic advantages over CNB and indications for the utilization of VAB are discussed. VAB additionally has an expanding role as a tool for breast lesion excision.

Fine-needle aspiration and core biopsy in the diagnosis of breast lesions: A comparison and review of the literature

In recent times, the diagnosis of breast lesions has mostly become dependent on core needle biopsies (CNBs) with a gradual reduction in the rate of performing fine-needle aspiration cytology (FNAC). Both the procedures have their pros and cons and outsmart each other taking into account different parameters. Both the methods are found to be fraught with loopholes, taking into account different performance indices, diagnostic accuracy and concordance, patient benefit, and cost-effectiveness. Unlike the popular belief of an absolute superiority of CNB over FNAC, the literature review does not reveal a very distinct demarcation in many aspects. We recommend judicious use of these diagnostic modalities in resource-limited settings and screening programs taking into account parameters such as palpability and availability of an experienced cytopathologist.

HER 2 immunohistochemistry for breast cancer cell blocks can be used in the same way as that used for histological specimens

Background

Human epidermal growth factor receptor 2 (HER2) testing of samples from recurrent or metastatic breast cancer is recommended by the 2013 update of the American Society of Clinical Oncology/College of American Pathologists guidelines. Although cytological analysis can be applied to several types of metastatic lesions, the practical method for HER2 testing of cytological specimens is yet to be resolved. We conducted immunohistochemical (IHC) staining for HER2 in breast cancer cell blocks (CBs) and compared the results with those from the corresponding histological specimens. In cases of discrepancy between the two types of specimen, the bright‐field HER2 dual in situ hybridization (DISH) assay was performed.

Methods

CBs were prepared from 54 surgically excised breast cancers. The cells were fixed in 10% buffered formalin and embedded in paraffin. A Ventana BenchMark ULTRA (Roche Diagnostics) with anti‐HER‐2/neu (4B5) rabbit monoclonal primary antibody and INFORM HER2/neu Dual ISH DNA Probe Cocktail was used for the assays.

Results

Successful results were obtained in 52 of 54 CBs. Forty cases showed agreement between CBs and the histological specimens. No discrepancy was observed between the two types of specimens in cases where HER2 expression was positive. IHC results of CB in 12 discrepant cases were HER2 intermediate or negative. The DISH results of 11 of these cases were negative.

Conclusion

IHC staining of HER2 for breast cancer CBs can be used in the same way as that used for histological specimens, although the number of equivocal cases in CBs is greater than that in histological specimens. Diagn. Cytopathol. 2016;44:274–279. © 2016 The Authors Diagnostic Cytopathology Published by Wiley Periodicals, Inc.

Bright-field HER2 dual in situ hybridization (DISH) assay on breast cancer cell blocks: a comparative study with histological sections

BACKGROUND

HER2 testing for samples from recurrent or metastatic disease is recommended by the 2013 update of the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guidelines and cytological analysis can be applied to several types of metastatic lesions. However, the practical method to assess the HER2 testing of breast cancer cytology specimens has yet to be resolved. Therefore, we conducted the bright-field HER2 dual in situ hybridization (DISH) assay on cell blocks (CBs) prepared from breast cancer cell samples as a validation study before clinical use.

METHODS

CBs were prepared from tumor cell samples collected from 54 surgically excised breast tumors. The cells were fixed in 10 % buffered formalin for 16-28 h, and embedded in paraffin. The INFORM HER2/neu Dual ISH DNA Probe Cocktail was used for the DISH assay on the Ventana BenchMark ULTRA (Roche Diagnostics).

RESULTS

Successful results were obtained in 51 of 54 CB specimens, and the results from the CB specimens were in agreement with those from the histological sections in 48 of the 51 cases (concordance rate, 94 %; kappa, 0.846). The intraclass correlation coefficient (ICC) between the CB and histological specimens in the continuous HER2/CEP17 signal count ratio was 0.89 (95 % CI 0.81-0.93), and the Pearson's CC was 0.91 (95 % CI 0.85-0.94).

CONCLUSION

The HER2 DISH assay, utilizing 10 % buffered formalin-fixed CB, would be a reliable and ideal method to assess the HER2 gene status of breast cancer cytological specimens.

Assessment of Hormone Receptor and Human Epidermal Growth Factor Receptor 2 Status in Breast Carcinoma Using Thin-Prep Cytology Fine Needle Aspiration Cytology FISH Experience From China

Estrogen receptor (ER) and progesterone receptor (PR) overexpression can be used to predict patient prognosis in breast cancer (BC). Human epidermal growth factor receptor 2 (HER2) is a reliable predictive marker in invasive breast cancer (IBC). Thin-Prep (TP) specimens are commonly utilized for immunocytochemistry (ICC) in fine needle aspiration cytology (FNAC). Thus, we sought to investigate if the incorporation of molecular diagnosis performed on TP-processed specimens is applicable in clinical practice. Hormone receptors (HRs) and HER2 immunocytochemistry was performed on 542 primary breast cancer FNAC specimens using the TP method. One hundred fourteen HER2 fluorescence in situ hybridization (FISH) analyses were performed on HER2 ICC 2+ FNAC specimens and the corresponding tissue samples. HRs results of TP slides and those of formalin-fixed paraffin-embedded (FFPE) slides were correlated well for ER (concordance rate =  3.3%, kappa value = 0.85) and PR (concordance rate = 88.6%, kappa value = 0.75). HER2 results for the TP slides and those of the matched FFPE slides also correlated well (concordance rate = 80.0%, kappa value = 0.62). The specificity of HER2 was 97.3%; however, the sensitivity was only 67.1%. Cytological specimens and histological samples showed a strong correlation (concordance rate = 99.1%, kappa value = 0.98) while being used to evaluate HER2 gene amplification. FNAC is a minimally invasive technique that can be used as an alternative method to collect tissue especially in cases where an excisional or core biopsy is difficult to obtain, or when recurrence is present. The results of ICC HRs in FNAC TP specimens may be used instead, but HER2 assessment may not be reliable enough for clinical use. FISH testing is necessary in this setting.

Efficacy of liquid-based cytology versus conventional smears in FNA samples

BACKGROUND

Liquid-based cytology (LBC) is fast becoming a useful method in evaluating both gynecological and non-gynecological preparations, including fine needle aspiration (FNA) cytology. Even distribution of cells, decreasing obscuring background elements like blood and mucus, well preserved nuclear and cytoplasmic details and rapid fixation helps in better visualization of cells.

AIM

This study was conducted to asses the diagnostic accuracy of liquid-based cytology versus conventional smears in fine needle aspiration samples.

STUDY DESIGN

In this prospective study, we had 110 cases, including 30 cases of breast, 40 of lymph node, 10 of salivary glands, 18 of thyroid and 12 of bone and soft tissue. In each case, two passes were performed. The first pass was for conventional preparation (CP) and the second pass yielded material for thin-prep (TP) preparation. Both CP and TP smears were compared for cellularity, background blood and necrotic cell debris, cell architecture, informative background, presence of a monolayer of cells and nuclear and cytoplasmic details by a semiquantitative scoring system. Wilcoxon's signed rank test on an SPSS program was used for statistical analysis.

RESULTS

Diagnostic accuracy was better in LBC smears compared with CP smears due to lack of background debris and better cell morphology, which was performed according to Wilcoxon's signed rank test, yielding a P-value of <0.001. However, in some cases, because of a decrease in cell size, clustering and altered background in LBC, a support of CP was essential.

CONCLUSION

LBC performed on FNA samples can be a simple and valuable technique. Only in few selected cases, where background factor is an essential diagnostic clue, a combination of both CP and TP is necessary.

Correlation of HER2 gene status assessment by fluorescence in situ hybridization between histological sections and cytological specimens of breast cancer

BACKGROUND

While HER2 gene detection in cytological specimens using fluorescence in situ hybridization (FISH) has been reported, the appropriate criteria for such specimens remain controversial.

METHODS

Fine needle aspiration (FNA) samples collected from surgically resected breast cancer specimens were rinsed in a cytopreservative solution containing fixative. Then, slides of the FNA samples were prepared by liquid-based cytology (LBC) (ThinPrep system, Hologic) according to the manufacturer's instructions, and a PathVision HER2 DNA probe kit (Abbott) was used for FISH staining. The results were evaluated using an automated MetaCyte imaging system (MetaSystems, Altlussheim, Germany). HER2 gene amplification was scored using the HER2/chromosome enumeration probe 17 (CEP17) signal count ratio as follows: amplified, >2.2; equivocal, 1.8-2.2; and unamplified, <1.8. The cytology results were compared with the histology results from concordant cases.

RESULTS

Successful results were obtained in 98 of 100 cases, and results from the FNA specimens were in agreement with those from the histological sections in 97 of these 98 cases (accuracy rate, 99 %; kappa, 0.962).

CONCLUSIONS

FISH-based assessment of the HER2 gene status is consistent between histological sections and cytological specimens of breast cancer.

Low concordance of biomarkers in histopathological and cytological material from breast cancer

AIMS

The aim of this study was to investigate in primary breast cancer the congruency of routine clinical predictive biomarker evaluations, including ER, PR and Ki67, obtained using immunocytochemistry (ICC) and immunohistochemistry (IHC).

METHODS AND RESULTS

Clinicopathological data were collected on all women diagnosed with primary breast cancer at Karolinska University Hospital in 2011. A total of 346 patients were included in a retrospective paired comparison of predictive biomarker evaluations on direct smear ICC and IHC. This showed a low congruency between findings with the two methods, especially evident for Ki67 (κ = 0.35-0.42). By suggested adjustments to ICC cut-offs, we managed to improve the inter-rater agreement of Ki67 classification slightly to κ = 0.46.

CONCLUSIONS

Our findings suggest that routine clinical ICC and IHC evaluations of predictive biomarkers produce discordant results. Consequently, basing therapeutic decisions on cytology with cut-offs defined for IHC induces a risk that patients will receive suboptimal therapy. However, our analysis shows that local adjustments to biomarker cut-off levels may improve congruency and increase the probability of correct classifications.

Fine-needle aspiration cytology can play a role in neoadjuvant chemotherapy in operable breast cancer

Despite the fact that CNB has been progressively replaced by FNAC in the investigation of nonpalpable lesions or microcalcifications without a clinical or radiological mass lesion, FNAC has yet a role in palpable lesions provided it is associated with the triple diagnosis and experienced cytologist. In these conditions, FNAC is a safe, effective, economical, and accurate technique for breast cancer evaluation. Numerous literature reviews and meta-analyses illustrated the advantages and disadvantages of both methods CNB and FNAC. The difference does not seem significant when noninformative and unsatisfactory FNAC was excluded. Recently, cytological methods using liquid-based cytology (LBC) technology improve immunocytological and molecular tests with the same efficiency as classical immunohistochemistry. The indications of FNAC were, for palpable lesions, relative contraindication of CNB (elderly or frailty), staging of multiple nodules in conjunction or not with CNB, staging of lymph node status, newly appearing lesion in patient under neoadjuvant treatment, decreasing of anxiety with a rapid diagnosis, evaluation of biomarkers and new biomarkers, and chronological evaluation of biomarker following the neoadjuvant therapy response.

Identifying targets for the restoration and reactivation of BRM

Brahma (BRM) is a novel anticancer gene, which is frequently inactivated in a variety of tumor types. Unlike many anticancer genes, BRM is not mutated, but rather epigenetically silenced. In addition, histone deacetylase complex (HDAC) inhibitors are known to reverse BRM silencing, but they also inactivate it via acetylation of its C-terminus. High-throughput screening has uncovered many compounds that are effective at pharmacologically restoring BRM and thereby inhibit cancer cell growth. As we do not know which specific proteins, if any, regulate BRM, we sought to identify the proteins, which underlie the epigenetic suppression of BRM. By selectively knocking down each HDAC, we found that HDAC3 and HDAC9 regulate BRM expression, whereas HDAC2 controls its acetylation. Similarly, we ectopically overexpressed 21 different histone acetyltransferases and found that KAT6A, KAT6B and KAT7 induce BRM expression, whereas KAT2B and KAT8 induce its acetylation. We also investigated the role of two transcription factors (TFs) linked to either BRM (GATA3) or HDAC9 (MEF2D) expression. Knockdown of either GATA3 and/or MEF2D downregulated HDAC9 and induced BRM. As targets for molecular biotherapy are typically uniquely, or simply differentially expressed in cancer cells, we also determined if any of these proteins are dysregulated. However, by sequencing, no mutations were found in any of these BRM-regulating HDACs, HATs or TFs. We selectively knocked down GATA3, MEF2D, HDAC3 and HDAC9, and found that each gene-specific knockdown induced growth inhibition. We observed that both GATA3 and HDAC9 were greatly overexpressed only in BRM-negative cell lines indicating that HDAC9 may be a good target for therapy. We also found that the mitogen-activated protein (MAP) kinase pathway regulates both BRM acetylation and BRM silencing as MAP kinase pathway inhibitors both induced BRM as well as caused BRM deacetylation. Together, these data identify a cadre of key proteins, which underlie the epigenetic regulation of BRM.

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.

Systematic review on hormone receptor testing in breast cancer

Assessment of hormone receptors (estrogen and progesterone) helps to direct therapy for women with breast cancer. Immunohistochemistry is most commonly used to assess hormone receptor status and it is essential that these tests are performed accurately and reliably within and across laboratories. The overall purpose of this guideline is to improve the quality and accuracy of hormone receptor testing and its utility as a prognostic and predictive marker for invasive and in situ breast cancer. Medline, EMBASE, the Cochrane Database of Systematic Reviews, and abstracts from the San Antonio Breast Cancer Symposium were searched. An environmental scan of the internet and of international guideline developers and key organizations was performed. Preanalytic elements such as the collection, fixation, and storage of samples, and analytic elements such as selection of antibodies and scoring methods that seem to offer the best results for immunohistochemical assessment of hormone receptors are presented. Proficiency testing or quality assurance of immunohistochemistry is described.

Comparison of the oestrogen and progesterone receptor status in primary breast carcinomas as evaluated by immunohistochemistry and immunocytochemistry: a consecutive series of 267 patients

OBJECTIVE

The use of cytological specimens to evaluate tumour biomarkers in metastatic breast cancer lesions has attracted increased interest because of the considerable number of reports that have shown discordance between the primary tumour and metastatic lesion. Oestrogen receptor (ER) and progesterone receptor (PgR) assays are crucial for the management of patients with breast cancer, in both adjuvant and palliative settings. The aim of this study was to compare the ER and PgR immunocytochemical analysis of fine needle aspiration (FNA) samples with the immunohistochemistry (IHC) of surgical specimens and core biopsies from primary breast cancers.

METHODS

The FNA specimens were prepared as cell blocks (n = 25) or ThinPreps (n = 258) for the immunocytochemistry (IC) ER and PgR analyses. Sixteen patients were excluded because of lack of follow-up (n = 1), neoadjuvant therapy (n = 3) or cell counts in their fine needle aspirates that were too low (n = 12). The results of IC on 25 cell blocks and 242 ThinPreps were compared with IHC on the corresponding core needle biopsies (n = 16) or excised tumours (n = 251). The ER and PgR status was defined as negative (when less than 10% of the nuclei were stained) or positive (when equal or more than 10% of the nuclei were stained). Kappa statistics were used to evaluate the concordance.

RESULTS

The ER concordance was 98% with ThinPrep (κ = 0.93) and 92% with cell block (κ = 0.82). The corresponding values for PgR were 96% (κ = 0.91) and 96% (κ = 0.92).

CONCLUSIONS

Our results confirm that, in cases in which biopsies or surgical specimens are not available, IC (with either cell block or ThinPrep techniques) is a reliable method for the determination of the ER and PgR status performed under strict conditions using primary breast carcinomas, and is therefore potentially useful in metastatic settings.

Cancer care Ontario guideline recommendations for hormone receptor testing in breast cancer

Hormone receptor testing (oestrogen and progesterone) in breast cancer at the time of primary diagnosis is used to guide treatment decisions. Accurate and standardised testing methods are critical to ensure the proper classification of the patient's hormone receptor status. Recommendations were developed to improve the quality and accuracy of hormone receptor testing based on a systematic review conducted jointly by the American Society of Clinical Oncology/College of American Pathologists and Cancer Care Ontario's Program in Evidence-Based Care. Evidence-based recommendations were formulated to set standards for optimising immunohistochemistry in assessing hormone receptor status, as well as assuring quality and proficiency between and within laboratories. A formal external review was conducted to validate the relevance of these recommendations. It is anticipated that widespread adoption of these guidelines will further improve the accuracy of hormone receptor testing in Canada.

Liquid based material from fine needle aspirates from breast carcinomas offers the possibility of long-time storage without significant loss of immunoreactivity of estrogen and progesterone receptors

BACKGROUND

Estrogen receptor (ER) status and progesterone receptor (PgR) status are strong prognostic and predictive markers in breast carcinomas. Steroid receptors are fragile and optimal handling of both cytological and histological material, including fixation, is crucial. Liquid based material offers the possibility to prepare a number of slides from one lesion and is increasingly being used for immunocytochemistry. It also offers the possibility to prepare several smears and to store these at different temperatures as well as storing residual material in the liquid.

MATERIALS AND METHODS

The samples consisted of fine needle aspirate material from 53 breast carcinomas. Direct smears and liquid based preparations were used in parallel for immunocytochemical detection of ER and PgR receptor status. Slides from liquid suspensions were stored at -20°C and -74°C for 3 and 6 months, respectively. Direct smears were fixed primarily in 4% formalin. Liquid based specimens were post-fixed in 4% formalin. All specimens were subjected to microwave-stimulated epitope retrieval. Antibody concentrations were ER 1:150 and PgR 1:200 for both preparation methods. The immunostaining program was identical for both the methods.

RESULTS

Liquid based specimens had a statistically non-significant higher percentage of positive cases compared to direct smears. Specimens prepared from liquid suspensions and stored at -20°C and -74°C for 3 and 6 months, respectively, showed a virtually unchanged ER and PgR reactivity (P = 0.002).

CONCLUSIONS

Liquid suspensions and liquid based slide preparations seem to offer an optimal pre-fixation and preservation of ER/PgR in breast carcinoma cells. Post-fixation with 4% formalin followed by microwave-stimulated epitope retrieval before immunostaining is recommended. Long-time storage of liquid based specimens at -20°C or -74°C for at least 6 months without significant loss of immunoreactivity is feasible. They may be used as internal positive and negative controls.

Preoperative cytological and histological diagnosis of breast lesions: A critical review

BACKGROUND

Non-operative pathology diagnoses constitute an essential part of the work-up of breast lesions. With fine needle aspiration (FNA) and core needle biopsy (CNB) both having unique advantages, there is an increasing acceptance of CNB. This paper aims to outline the scientific basis of this trend. Additionally, we provide an update on novel techniques that derive cytological specimens from CNB (i.e., touch imprint (TI) and core wash (CW) cytology) in an attempt to get the best of both worlds.

METHODS

In addition to using the authors' experience, we performed a search of the Medline database combining the search terms "breast cancer diagnosis", "core needle biopsy", "fine needle aspiration", "touch imprint cytology", "core wash cytology" and "complications". We defined a conclusive non-operative diagnosis as "malignant" in lesions that were malignant on follow-up and "benign" in lesions that were benign on follow-up.

RESULTS

CNB was more often conclusive than FNA in benign and malignant lesions in 4 prospective studies. Although the more rapid diagnoses by FNA result in less patient anxiety during diagnostic work-up, CNB allows for fairly reliable estimation of invasion, histological type, grade, and receptor expression. CW and TI cytology seem promising techniques with conclusiveness rates that are roughly comparable to that of FNA.

CONCLUSIONS

All new suspicious breast lesions require careful non-operative investigation by CNB. However, additional cytological assessment by FNA can still be useful as a same-day diagnosis decreases patient anxiety and facilitates surgical treatment planning. TI and CW cytology techniques are promising same-day diagnosis modalities.