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Bocklage T, Cornea V, Hickey C, Miller J, Moss J, Chambers M, Bachert SE. Ki-67 Testing in Breast Cancer: Assessing Variability With Scoring Methods and Specimen Types and the Potential Subsequent Impact on Therapy Eligibility. Appl Immunohistochem Mol Morphol 2024; 32:119-124. [PMID: 38450704 DOI: 10.1097/pai.0000000000001188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 01/26/2024] [Indexed: 03/08/2024]
Abstract
Abemaciclib was originally FDA approved for patients with ER-positive/HER2-negative breast cancer with Ki-67 expression ≥20%. However, there were no guidelines provided on which specimen to test or which scoring method to use. We performed a comprehensive study evaluating the variation in Ki-67 expression in breast specimens from 50 consecutive patients who could have been eligible for abemaciclib therapy. Three pathologists with breast expertise each performed a blinded review with 3 different manual scoring methods [estimated (EST), unweighted (UNW), and weighted (WT) (WT recommended by the International Ki-67 in Breast Cancer Working Group)]. Quantitative image analysis (QIA) using the HALO platform was also performed. Three different specimen types [core needle biopsy (CNB) (n=63), resection (RES) (n=52), and axillary lymph node metastasis (ALN) (n=50)] were evaluated for each patient. The average Ki-67 for all specimens was 14.68% for EST, 14.46% for UNW, 14.15% for WT, and 11.15% for QIA. For the manual methods, the range between the lowest and highest Ki-67 for each specimen between the 3 pathologists was 8.44 for EST, 5.94 for WT, and 5.93 for UNW. The WT method limited interobserver variability with ICC1=0.959 (EST ICC1=0.922 and UNW=0.949). Using the aforementioned cutoff of Ki-67 ≥20% versus <20% to determine treatment eligibility, the averaged EST method yields 20 of 50 patients (40%) who would have been treatment-eligible, versus 15 (30%) for the UNW, 17 (34%) for the WT, and 12 (24%) for the QIA. There was no statistically significant difference in Ki-67 among the 3 specimen types. The average Ki-67 difference was 4.36 for CNB vs RES, 6.95 for CNB versus ALN, and RES versus ALN (P=0.93, 0.99, and 0.94, respectively). Our study concludes that further refinement in Ki-67 scoring is advisable to reduce clinically significant variation.
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Affiliation(s)
| | | | | | | | - Jessica Moss
- Internal Medicine, Medical Oncology, University of Kentucky, Lexington, KY
| | - Mara Chambers
- Internal Medicine, Medical Oncology, University of Kentucky, Lexington, KY
| | - S Emily Bachert
- Department of Pathology, Brigham & Women's Hospital and Harvard Medical School, Boston, MA
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2
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Vakharia K, Hasegawa H, Graffeo C, Noureldine MHA, Cohen-Cohen S, Perry A, Carlson ML, Driscoll CLW, Peris-Celda M, Van Gompel JJ, Link MJ. Predictive Value of K i -67 Index in Evaluating Sporadic Vestibular Schwannoma Recurrence: Systematic Review and Meta-analysis. J Neurol Surg B Skull Base 2023; 84:119-128. [PMID: 36895813 PMCID: PMC9991525 DOI: 10.1055/a-1760-2126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 01/31/2022] [Indexed: 10/19/2022] Open
Abstract
Introduction K i -67 is often used as a proliferation index to evaluate how aggressive a tumor is and its likelihood of recurrence. Vestibular schwannomas (VS) are a unique benign pathology that lends itself well to evaluation with K i -67 as a potential marker for disease recurrence or progression following surgical resection. Methods All English language studies of VSs and K i -67 indices were screened. Studies were considered eligible for inclusion if they reported series of VSs undergoing primary resection without prior irradiation, with outcomes including both recurrence/progression and K i -67 for individual patients. For published studies reporting pooled K i -67 index data without detailed by-patient values, we contacted the authors to request data sharing for the current meta-analysis. Studies reporting a relationship between K i -67 index and clinical outcomes in VS for which detailed patients' outcomes or K i -67 indices could not be obtained were incorporated into the descriptive analysis, but excluded from the formal (i.e., quantitative) meta-analysis. Results A systematic review identified 104 candidate citations of which 12 met inclusion criteria. Six of these studies had accessible patient-specific data. Individual patient data were collected from these studies for calculation of discrete study effect sizes, pooling via random-effects modeling with restricted maximum likelihood, and meta-analysis. The standardized mean difference in K i -67 indices between those with and without recurrence was calculated as 0.79% (95% confidence interval [CI]: 0.28-1.30; p = 0.0026). Conclusion K i -67 index may be higher in VSs that demonstrate recurrence/progression following surgical resection. This may represent a promising means of evaluating tumor recurrence and potential need for early adjuvant therapy for VSs.
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Affiliation(s)
- Kunal Vakharia
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota, United States.,Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, Florida, United States
| | - Hirotaka Hasegawa
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota, United States.,Department of Neurosurgery, Tokyo University, Tokyo, Japan
| | - Christopher Graffeo
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota, United States.,Department of Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona, United States
| | - Mohammad H A Noureldine
- Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, Florida, United States
| | - Salomon Cohen-Cohen
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota, United States
| | - Avital Perry
- Department of Neurosurgery, Sheba Medical Center, Tel Aviv, Israel
| | - Matthew L Carlson
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota, United States.,Department of Otolaryngology-Head and Neck Surgery, Mayo Clinic, Rochester, Minnesota, United States
| | - Colin L W Driscoll
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota, United States.,Department of Otolaryngology-Head and Neck Surgery, Mayo Clinic, Rochester, Minnesota, United States
| | - Maria Peris-Celda
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota, United States
| | - Jamie J Van Gompel
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota, United States
| | - Michael J Link
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota, United States.,Department of Otolaryngology-Head and Neck Surgery, Mayo Clinic, Rochester, Minnesota, United States
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Robbins CJ, Fernandez AI, Han G, Wong S, Harigopal M, Podoll M, Singh K, Ly A, Kuba MG, Wen H, Sanders MA, Brock J, Wei S, Fadare O, Hanley K, Jorns J, Snir OL, Yoon E, Rabe K, Soong TR, Reisenbichler ES, Rimm DL. Multi-institutional Assessment of Pathologist Scoring HER2 Immunohistochemistry. Mod Pathol 2023; 36:100032. [PMID: 36788069 PMCID: PMC10278086 DOI: 10.1016/j.modpat.2022.100032] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/01/2022] [Accepted: 09/21/2022] [Indexed: 01/19/2023]
Abstract
The HercepTest was approved 20+ years ago as the companion diagnostic test for trastuzumab in human epidermal growth factor 2 (HER2) or ERBB2 gene-amplified/overexpressing breast cancers. Subsequent HER2 immunohistochemistry (IHC) assays followed, including the now most common Ventana 4B5 assay. Although this IHC assay has become the clinical standard, its reliability, reproducibility, and accuracy have largely been approved and accepted on the basis of concordance among small numbers of pathologists without validation in a real-world setting. In this study, we evaluated the concordance and interrater reliability of scoring HER2 IHC in 170 breast cancer biopsies by 18 breast cancer-specialized pathologists from 15 institutions. We used the Observers Needed to Evaluate Subjective Tests method to determine the plateau of concordance and the minimum number of pathologists needed to estimate interrater agreement values for large numbers of raters, as seen in the real-world setting. We report substantial discordance within the intermediate categories (<1% agreement for 1+ and 3.6% agreement for 2+) in the 4-category HER2 IHC scoring system. The discordance within the IHC 0 cases is also substantial with an overall percent agreement (OPA) of only 25% and poor interrater reliability metrics (0.49 Fleiss' kappa, 0.55 intraclass correlation coefficient). This discordance can be partially reduced by using a 3-category system (28.8% vs 46.5% OPA for 4-category and 3-category scoring systems, respectively). Observers Needed to Evaluate Subjective Tests plots suggest that the OPA for the task of determining a HER2 IHC score 0 from not 0 plateaus statistically around 59.4% at 10 raters. Conversely, at the task of scoring HER2 IHC as 3+ or not 3+ pathologists' concordance was much higher with an OPA that plateaus at 87.1% with 6 raters. This suggests that legacy HER2 IHC remains valuable for finding the patients in whom the ERBB2 gene is amplified but unacceptably discordant in assigning HER2-low or HER2-negative status for the emerging HER2-low therapies.
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Affiliation(s)
- Charles J Robbins
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
| | - Aileen I Fernandez
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
| | - Gang Han
- Department of Epidemiology & Biostatistics, Texas A and M University, College Station, Texas
| | - Serena Wong
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
| | - Malini Harigopal
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut
| | - Mirna Podoll
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Kamaljeet Singh
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island
| | - Amy Ly
- Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts
| | - M Gabriela Kuba
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Hannah Wen
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Mary Ann Sanders
- Department of Pathology, Norton Healthcare, Louisville, Kentucky
| | - Jane Brock
- Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts
| | - Shi Wei
- Department of Pathology, University of Kansas Medical Center, Kansas City, Kansas
| | - Oluwole Fadare
- Department of Pathology, University of California San Diego, San Diego, California
| | - Krisztina Hanley
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - Julie Jorns
- Department of Pathology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Olivia L Snir
- Department of Pathology, Providence Health & Services, Portland, Oregon
| | - Esther Yoon
- Department of Pathology, MD Anderson, Cancer Center, Houston, Texas
| | - Kim Rabe
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota
| | - T Rinda Soong
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Emily S Reisenbichler
- Department of Pathology, SSM Health Saint Louis University Hospital, St. Louis, Missouri
| | - David L Rimm
- Department of Pathology, Yale School of Medicine, New Haven, Connecticut; Department of Medicine (Oncology), Yale School of Medicine, New Haven, Connecticut.
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Elie N, Giffard F, Blanc-Fournier C, Morice PM, Brachet PE, Dutoit S, Plancoulaine B, Poulain L. Impact of automated methods for quantitative evaluation of immunostaining: Towards digital pathology. Front Oncol 2022; 12:931035. [PMID: 36303844 PMCID: PMC9592864 DOI: 10.3389/fonc.2022.931035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 09/20/2022] [Indexed: 11/28/2022] Open
Abstract
Introduction We sought to develop a novel method for a fully automated, robust quantification of protein biomarker expression within the epithelial component of high-grade serous ovarian tumors (HGSOC). Rather than defining thresholds for a given biomarker, the objective of this study in a small cohort of patients was to develop a method applicable to the many clinical situations in which immunomarkers need to be quantified. We aimed to quantify biomarker expression by correlating it with the heterogeneity of staining, using a non-subjective choice of scoring thresholds based on classical mathematical approaches. This could lead to a universal method for quantifying other immunohistochemical markers to guide pathologists in therapeutic decision-making. Methods We studied a cohort of 25 cases of HGSOC for which three biomarkers predictive of the response observed ex vivo to the BH3 mimetic molecule ABT-737 had been previously validated by a pathologist. We calibrated our algorithms using Stereology analyses performed by two experts to detect immunohistochemical staining and epithelial/stromal compartments. Immunostaining quantification within Stereology grids of hexagons was then performed for each histological slice. To define thresholds from the staining distribution histograms and to classify staining within each hexagon as low, medium, or high, we used the Gaussian Mixture Model (GMM). Results Stereology analysis of this calibration process produced a good correlation between the experts for both epithelium and immunostaining detection. There was also a good correlation between the experts and image processing. Image processing clearly revealed the respective proportions of low, medium, and high areas in a single tumor and showed that this parameter of heterogeneity could be included in a composite score, thus decreasing the level of discrepancy. Therefore, agreement with the pathologist was increased by taking heterogeneity into account. Conclusion and discussion This simple, robust, calibrated method using basic tools and known parameters can be used to quantify and characterize the expression of protein biomarkers within the different tumor compartments. It is based on known mathematical thresholds and takes the intratumoral heterogeneity of staining into account. Although some discrepancies need to be diminished, correlation with the pathologist’s classification was satisfactory. The method is replicable and can be used to analyze other biological and medical issues. This non-subjective technique for assessing protein biomarker expression uses a fully automated choice of thresholds (GMM) and defined composite scores that take the intra-tumor heterogeneity of immunostaining into account. It could help to avoid the misclassification of patients and its subsequent negative impact on therapeutic care.
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Affiliation(s)
- Nicolas Elie
- Normandie Univ, UNICAEN, Federative Structure 4207 ‘Normandie Oncologie’, PLATON Services Unit, Virtual’His platform, Caen, France
- Normandie Univ, UNICAEN, Federative Structure 4207 ‘Normandie Oncologie’, PLATON Services Unit, Caen, France
| | - Florence Giffard
- Normandie Univ, UNICAEN, Federative Structure 4207 ‘Normandie Oncologie’, PLATON Services Unit, Virtual’His platform, Caen, France
- Normandie Univ, UNICAEN, Federative Structure 4207 ‘Normandie Oncologie’, PLATON Services Unit, Caen, France
- Normandie Univ, UNICAEN, Inserm U1086 ANTICIPE, Interdisciplinary Research Unit for Cancer Prevention and Treatment, Federative Structure 4207 ‘Normandie Oncologie’, F. Baclesse Comprehensive Cancer Centre, Caen, France
- UNICANCER, F. Baclesse Comprehensive Cancer Centre, Caen, France
| | - Cécile Blanc-Fournier
- UNICANCER, F. Baclesse Comprehensive Cancer Centre, Caen, France
- UNICANCER, F. Baclesse Comprehensive Cancer Centre, Biopathology Department, Caen, France
| | - Pierre-Marie Morice
- Normandie Univ, UNICAEN, Inserm U1086 ANTICIPE, Interdisciplinary Research Unit for Cancer Prevention and Treatment, Federative Structure 4207 ‘Normandie Oncologie’, F. Baclesse Comprehensive Cancer Centre, Caen, France
| | | | - Soizic Dutoit
- Normandie Univ, UNICAEN, Inserm U1086 ANTICIPE, Interdisciplinary Research Unit for Cancer Prevention and Treatment, Federative Structure 4207 ‘Normandie Oncologie’, F. Baclesse Comprehensive Cancer Centre, Caen, France
| | - Benoît Plancoulaine
- Normandie Univ, UNICAEN, Inserm U1086 ANTICIPE, Interdisciplinary Research Unit for Cancer Prevention and Treatment, Federative Structure 4207 ‘Normandie Oncologie’, F. Baclesse Comprehensive Cancer Centre, Caen, France
- Department of Pathology, Forensic Medicine and Pharmacology, Institute of Biomedical Sciences of the Faculty of Medicine, Vilnius University, Vilnius, Lithuania
- *Correspondence: Benoît Plancoulaine, ; Laurent Poulain,
| | - Laurent Poulain
- Normandie Univ, UNICAEN, Federative Structure 4207 ‘Normandie Oncologie’, PLATON Services Unit, Caen, France
- Normandie Univ, UNICAEN, Inserm U1086 ANTICIPE, Interdisciplinary Research Unit for Cancer Prevention and Treatment, Federative Structure 4207 ‘Normandie Oncologie’, F. Baclesse Comprehensive Cancer Centre, Caen, France
- UNICANCER, F. Baclesse Comprehensive Cancer Centre, Caen, France
- *Correspondence: Benoît Plancoulaine, ; Laurent Poulain,
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Should Ki-67 be adopted to select breast cancer patients for treatment with adjuvant abemaciclib? Ann Oncol 2021; 33:234-238. [PMID: 34942341 DOI: 10.1016/j.annonc.2021.12.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/12/2021] [Indexed: 01/09/2023] Open
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6
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Cserni B, Bori R, Csörgő E, Oláh-Németh O, Pancsa T, Sejben A, Sejben I, Vörös A, Zombori T, Nyári T, Cserni G. The additional value of ONEST (Observers Needed to Evaluate Subjective Tests) in assessing reproducibility of oestrogen receptor, progesterone receptor, and Ki67 classification in breast cancer. Virchows Arch 2021; 479:1101-1109. [PMID: 34415429 PMCID: PMC8724065 DOI: 10.1007/s00428-021-03172-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/06/2021] [Accepted: 07/25/2021] [Indexed: 11/28/2022]
Abstract
The reproducibility of assessing potential biomarkers is crucial for their implementation. ONEST (Observers Needed to Evaluate Subjective Tests) has been recently introduced as a new additive evaluation method for the assessment of reliability, by demonstrating how the number of observers impact on interobserver agreement. Oestrogen receptor (ER), progesterone receptor (PR), and Ki67 proliferation marker immunohistochemical stainings were assessed on 50 core needle biopsy and 50 excision samples from breast cancers by 9 pathologists according to daily practice. ER and PR statuses based on the percentages of stained nuclei were the most consistently assessed parameters (intraclass correlation coefficients, ICC 0.918-0.996), whereas Ki67 with 5 different theoretical or St Gallen Consensus Conference-proposed cut-off values demonstrated moderate to good reproducibility (ICC: 0.625-0.760). ONEST highlighted that consistent tests like ER and PR assessment needed only 2 or 3 observers for optimal evaluation of reproducibility, and the width between plots of the best and worst overall percent agreement values for 100 randomly selected permutations of observers was narrow. In contrast, with less consistently evaluated tests of Ki67 categorization, ONEST suggested at least 5 observers required for more trustful assessment of reliability, and the bandwidth of the best and worst plots was wider (up to 34% difference between two observers). ONEST has additional value to traditional calculations of the interobserver agreement by not only highlighting the number of observers needed to trustfully evaluate reproducibility but also by highlighting the rate of agreement with an increasing number of observers and disagreement between the better and worse ratings.
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Affiliation(s)
| | - Rita Bori
- Department of Pathology, Bács-Kiskun County Teaching Hospital, Kecskemét, Hungary
| | - Erika Csörgő
- Department of Pathology, Bács-Kiskun County Teaching Hospital, Kecskemét, Hungary
| | | | - Tamás Pancsa
- Department of Pathology, University of Szeged, Szeged, Hungary
| | - Anita Sejben
- Department of Pathology, University of Szeged, Szeged, Hungary
| | - István Sejben
- Department of Pathology, Bács-Kiskun County Teaching Hospital, Kecskemét, Hungary
| | - András Vörös
- Department of Pathology, University of Szeged, Szeged, Hungary
| | - Tamás Zombori
- Department of Pathology, University of Szeged, Szeged, Hungary
| | - Tibor Nyári
- Department of Medical Physics and Informatics, University of Szeged, Szeged, Hungary
| | - Gábor Cserni
- Department of Pathology, Bács-Kiskun County Teaching Hospital, Kecskemét, Hungary. .,Department of Pathology, University of Szeged, Szeged, Hungary.
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7
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Thomas S, Kabir M, Butcher BE, Chou S, Mahajan H, Farshid G, Balleine R, Pathmanathan N. Interobserver concordance in visual assessment of Ki67 immunohistochemistry in surgical excision specimens from patients with lymph node-negative breast cancer. Breast Cancer Res Treat 2021; 188:729-737. [PMID: 33751322 DOI: 10.1007/s10549-021-06188-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 03/10/2021] [Indexed: 11/30/2022]
Abstract
PURPOSE This study aimed to determine the interobserver concordance of two methods for proliferation assessment in breast cancer using Ki67 immunohistochemistry. METHODS Ki67 was independently assessed in randomly selected tumour samples from patients with lymph node-negative breast cancer using two different methods: either cell counting or visual estimation of hot spot areas. For hot spot cell counting, positive and negative cell numbers were recorded for total cell counts of 300-500, 500-800 and 800-1000 cells. Visual estimation involved allocation of a score from 1 to 5 using a visual scale to estimate percentage positivity. Interobserver agreement for hot spot counting was calculated using a two-way fixed effects intraclass correlation model, and by using Cohen's kappa measure for visual assessment. Prognostic concordance between the two methods was also calculated using Cohen's kappa. RESULTS Samples from 96 patients were included in this analysis. Interobserver agreement for hot spot cell counting was excellent (> 0.75) across all three cell count ranges, with correlation coefficients of 0.88 (95% CI 0.84-0.92), 0.87 (95% CI 0.82-0.91) and 0.89 (95% CI 0.85-0.92), respectively. Interobserver agreement with visual estimation was greatest for hot spots compared with areas of intermediate or low proliferation, with kappa scores of 0.49, 0.42 and 0.40, respectively. Both assessment methods demonstrated excellent prognostic agreement. CONCLUSIONS Interobserver and prognostic concordance in Ki67 immunohistochemistry assessments was high using either hot spot cell counting or visual estimation, further supporting the utility and reproducibility of these cost-efficient methods to assess proliferation.
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Affiliation(s)
- Susanna Thomas
- Westmead Breast Cancer Institute, Westmead, NSW, 2145, Australia
- Western Sydney Local Health District, Westmead, NSW, 2145, Australia
- Australian Clinical Labs, Bella Vista, NSW, 2153, Australia
| | - Masrura Kabir
- Westmead Breast Cancer Institute, Westmead, NSW, 2145, Australia
- Western Sydney Local Health District, Westmead, NSW, 2145, Australia
| | - Belinda E Butcher
- WriteSource Medical Pty Ltd, Lane Cove, NSW, 2066, Australia
- School of Medical Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Shaun Chou
- Institute of Clinical Pathology and Medical Research, Pathology West, NSW Health Pathology, Sydney, NSW, 2145, Australia
| | - Hema Mahajan
- Institute of Clinical Pathology and Medical Research, Pathology West, NSW Health Pathology, Sydney, NSW, 2145, Australia
- Westmead Clinical School, University of Sydney, Sydney, NSW, 2145, Australia
| | - Gelareh Farshid
- SA Pathology, Royal Adelaide Hospital, Adelaide, SA, 5000, Australia
- School of Medical Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Rosemary Balleine
- Institute of Clinical Pathology and Medical Research, Pathology West, NSW Health Pathology, Sydney, NSW, 2145, Australia
- Faculty of Medicine and Health, Children's Medical Research Institute, University of Sydney, Westmead, NSW, 2145, Australia
| | - Nirmala Pathmanathan
- Westmead Breast Cancer Institute, Westmead, NSW, 2145, Australia.
- Western Sydney Local Health District, Westmead, NSW, 2145, Australia.
- Westmead Clinical School, University of Sydney, Sydney, NSW, 2145, Australia.
- Douglass Hanly Moir Pathology, Macquarie Park, NSW, 2113, Australia.
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8
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Jing N, Fang C, Williams DS. Validity and reliability of Ki-67 assessment in oestrogen receptor positive breast cancer. Pathology 2017; 49:371-378. [DOI: 10.1016/j.pathol.2017.02.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/22/2017] [Accepted: 02/05/2017] [Indexed: 12/24/2022]
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9
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Sinn HP, Schneeweiss A, Keller M, Schlombs K, Laible M, Seitz J, Lakis S, Veltrup E, Altevogt P, Eidt S, Wirtz RM, Marmé F. Comparison of immunohistochemistry with PCR for assessment of ER, PR, and Ki-67 and prediction of pathological complete response in breast cancer. BMC Cancer 2017; 17:124. [PMID: 28193205 PMCID: PMC5307758 DOI: 10.1186/s12885-017-3111-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 02/04/2017] [Indexed: 12/23/2022] Open
Abstract
Background Proliferation may predict response to neoadjuvant therapy of breast cancer and is commonly assessed by manual scoring of slides stained by immunohistochemistry (IHC) for Ki-67 similar to ER and PgR. This method carries significant intra- and inter-observer variability. Automatic scoring of Ki-67 with digital image analysis (qIHC) or assessment of MKI67 gene expression with RT-qPCR may improve diagnostic accuracy. Methods Ki-67 IHC visual assessment was compared to the IHC nuclear tool (AperioTM) on core biopsies from a randomized neoadjuvant clinical trial. Expression of ESR1, PGR and MKI67 by RT-qPCR was performed on RNA extracted from the same formalin-fixed paraffin-embedded tissue. Concordance between the three methods (vIHC, qIHC and RT-qPCR) was assessed for all 3 markers. The potential of Ki-67 IHC and RT-qPCR to predict pathological complete response (pCR) was evaluated using ROC analysis and non-parametric Mann-Whitney Test. Results Correlation between methods (qIHC versus RT-qPCR) was high for ER and PgR (spearman´s r = 0.82, p < 0.0001 and r = 0.86, p < 0.0001, respectively) resulting in high levels of concordance using predefined cut-offs. When comparing qIHC of ER and PgR with RT-qPCR of ESR1 and PGR the overall agreement was 96.6 and 91.4%, respectively, while overall agreement of visual IHC with RT-qPCR was slightly lower for ER/ESR1 and PR/PGR (91.2 and 92.9%, respectively). In contrast, only a moderate correlation was observed between qIHC and RT-qPCR continuous data for Ki-67/MKI67 (Spearman’s r = 0.50, p = 0.0001). Up to now no predictive cut-off for Ki-67 assessment by IHC has been established to predict response to neoadjuvant chemotherapy. Setting the desired sensitivity at 100%, specificity for the prediction of pCR (ypT0ypN0) was significantly higher for mRNA than for protein (68.9% vs. 22.2%). Moreover, the proliferation levels in patients achieving a pCR versus not differed significantly using MKI67 RNA expression (Mann-Whitney p = 0.002), but not with qIHC of Ki-67 (Mann-Whitney p = 0.097) or vIHC of Ki-67 (p = 0.131). Conclusion Digital image analysis can successfully be implemented for assessing ER, PR and Ki-67. IHC for ER and PR reveals high concordance with RT-qPCR. However, RT-qPCR displays a broader dynamic range and higher sensitivity than IHC. Moreover, correlation between Ki-67 qIHC and RT-qPCR is only moderate and RT-qPCR with MammaTyper® outperforms qIHC in predicting pCR. Both methods yield improvements to error-prone manual scoring of Ki-67. However, RT-qPCR was significantly more specific. Electronic supplementary material The online version of this article (doi:10.1186/s12885-017-3111-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hans-Peter Sinn
- Institute of Pathology, University of Heidelberg, Im Neuenheimer Feld 220-221, 69120, Heidelberg, Germany.
| | - Andreas Schneeweiss
- National Center for Tumor Diseases, University-Hospital Heidelberg, Im Neuenheimer Feld 460, 69120, Heidelberg, Germany
| | - Marius Keller
- Institute of Pathology, University of Heidelberg, Im Neuenheimer Feld 220-221, 69120, Heidelberg, Germany
| | | | - Mark Laible
- BioNTech Diagnostics GmbH, 55131, Mainz, Germany
| | - Julia Seitz
- National Center for Tumor Diseases, University-Hospital Heidelberg, Im Neuenheimer Feld 460, 69120, Heidelberg, Germany
| | - Sotirios Lakis
- STRATIFYER Molecular Pathology GmbH, Werthmannstr. 1c, 50935, Köln, Germany
| | - Elke Veltrup
- STRATIFYER Molecular Pathology GmbH, Werthmannstr. 1c, 50935, Köln, Germany
| | - Peter Altevogt
- German Cancer Research Center, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - Sebastian Eidt
- Department of Pathology, St. Elisabeth-Krankenhaus, Werthmannstr. 1c, 50935, Köln, Germany
| | - Ralph M Wirtz
- STRATIFYER Molecular Pathology GmbH, Werthmannstr. 1c, 50935, Köln, Germany.,Department of Pathology, St. Elisabeth-Krankenhaus, Werthmannstr. 1c, 50935, Köln, Germany
| | - Frederik Marmé
- National Center for Tumor Diseases, University-Hospital Heidelberg, Im Neuenheimer Feld 460, 69120, Heidelberg, Germany
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10
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Jensen K, Krusenstjerna-Hafstrøm R, Lohse J, Petersen KH, Derand H. A novel quantitative immunohistochemistry method for precise protein measurements directly in formalin-fixed, paraffin-embedded specimens: analytical performance measuring HER2. Mod Pathol 2017; 30:180-193. [PMID: 27767098 DOI: 10.1038/modpathol.2016.176] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 08/18/2016] [Accepted: 08/23/2016] [Indexed: 12/16/2022]
Abstract
In clinical routine pathology today, detection of protein in intact formalin-fixed, paraffin-embedded tissue is limited to immunohistochemistry, which is semi-quantitative. This study presents a new and reliable quantitative immunohistochemistry method, qIHC, based on a novel amplification system that enables quantification of protein directly in formalin-fixed, paraffin-embedded tissue by counting of dots. The qIHC technology can be combined with standard immunohistochemistry, and assessed using standard bright-field microscopy or image analysis. The objective was to study analytical performance of the qIHC method. qIHC was tested under requirements for an analytical quantitative test, and compared with ELISA and flow cytometry for quantitative protein measurements. Human epidermal growth factor receptor 2 (HER2) protein expression was measured in five different cell lines with HER2 expression from undetectable with immunohistochemistry to strong positive staining (IHC 3+). Repeatability, reproducibility, robustness, linearity, dynamic range, sensitivity, and quantification limits were evaluated. Reproducibility and robustness were assessed in a setup to resemble daily work in a laboratory using a commercial immunohistochemistry platform. In addition, qIHC was correlated to standard HER2 immunohistochemistry in 44 breast cancer specimens. For all evaluated parameters, qIHC performance was either comparable or better than the reference methods. Furthermore, qIHC has a lower limit of detection than both immunohistochemistry and the ELISA reference method, and demonstrated ability to measure HER2 accurately and precise within a large dynamic range. In conclusion, the results show that qIHC provides a sensitive, quantitative, accurate, and robust assay for measurement of protein expression in formalin-fixed, paraffin-embedded cell lines, and tissue.
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Affiliation(s)
- Kristian Jensen
- Dako Denmark A/S, an Agilent Technologies Company, Produktionsvej 42, Glostrup, Denmark
| | | | - Jesper Lohse
- Dako Denmark A/S, an Agilent Technologies Company, Produktionsvej 42, Glostrup, Denmark
| | - Kenneth H Petersen
- Dako Denmark A/S, an Agilent Technologies Company, Produktionsvej 42, Glostrup, Denmark
| | - Helene Derand
- Dako Denmark A/S, an Agilent Technologies Company, Produktionsvej 42, Glostrup, Denmark
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11
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Tretiakova MS, Wei W, Boyer HD, Newcomb LF, Hawley S, Auman H, Vakar-Lopez F, McKenney JK, Fazli L, Simko J, Troyer DA, Hurtado-Coll A, Thompson IM, Carroll PR, Ellis WJ, Gleave ME, Nelson PS, Lin DW, True LD, Feng Z, Brooks JD. Prognostic value of Ki67 in localized prostate carcinoma: a multi-institutional study of >1000 prostatectomies. Prostate Cancer Prostatic Dis 2016; 19:264-70. [PMID: 27136741 DOI: 10.1038/pcan.2016.12] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 02/17/2016] [Accepted: 03/08/2016] [Indexed: 01/07/2023]
Abstract
BACKGROUND Expanding interest in and use of active surveillance for early state prostate cancer (PC) has increased need for prognostic biomarkers. Using a multi-institutional tissue microarray resource including over 1000 radical prostatectomy samples, we sought to correlate Ki67 expression captured by an automated image analysis system with clinicopathological features and validate its utility as a clinical grade test in predicting cancer-specific outcomes. METHODS After immunostaining, the Ki67 proliferation index (PI) of tumor areas of each core (three cancer cores/case) was analyzed using a nuclear quantification algorithm (Aperio). We assessed whether Ki67 PI was associated with clinicopathological factors and recurrence-free survival (RFS) including biochemical recurrence, metastasis or PC death (7-year median follow-up). RESULTS In 1004 PCs (∼4000 tissue cores) Ki67 PI showed significantly higher inter-tumor (0.68) than intra-tumor variation (0.39). Ki67 PI was associated with stage (P<0.0001), seminal vesicle invasion (SVI, P=0.02), extracapsular extension (ECE, P<0.0001) and Gleason score (GS, P<0.0001). Ki67 PI as a continuous variable significantly correlated with recurrence-free, overall and disease-specific survival by multivariable Cox proportional hazard model (hazards ratio (HR)=1.04-1.1, P=0.02-0.0008). High Ki67 score (defined as ⩾5%) was significantly associated with worse RFS (HR=1.47, P=0.0007) and worse overall survival (HR=2.03, P=0.03). CONCLUSIONS In localized PC treated by radical prostatectomy, higher Ki67 PI assessed using a clinical grade automated algorithm is strongly associated with a higher GS, stage, SVI and ECE and greater probability of recurrence.
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Affiliation(s)
| | - W Wei
- MD Anderson Cancer Center, Houston, TX, USA
| | - H D Boyer
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - L F Newcomb
- University of Washington, Seattle, WA, USA.,Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - S Hawley
- Canary Foundation, Redwood City, CA, USA
| | - H Auman
- Canary Foundation, Redwood City, CA, USA
| | | | | | - L Fazli
- University of British Columbia, Vancouver, BC, Canada
| | - J Simko
- University of California at San Francisco, CA, USA
| | - D A Troyer
- Eastern Virginia Medical School, Norfolk, VA, USA
| | | | - I M Thompson
- University of Texas Health Sciences Center at San Antonio, TX, USA
| | - P R Carroll
- University of California at San Francisco, CA, USA
| | - W J Ellis
- University of Washington, Seattle, WA, USA.,Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - M E Gleave
- University of British Columbia, Vancouver, BC, Canada
| | - P S Nelson
- University of Washington, Seattle, WA, USA.,Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - D W Lin
- University of Washington, Seattle, WA, USA.,Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - L D True
- University of Washington, Seattle, WA, USA
| | - Z Feng
- MD Anderson Cancer Center, Houston, TX, USA
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12
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Zhong F, Bi R, Yu B, Yang F, Yang W, Shui R. A Comparison of Visual Assessment and Automated Digital Image Analysis of Ki67 Labeling Index in Breast Cancer. PLoS One 2016; 11:e0150505. [PMID: 26928407 PMCID: PMC4771161 DOI: 10.1371/journal.pone.0150505] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 02/14/2016] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Ki67 labeling index (LI) is critical for treatment options and prognosis evaluation in breast cancer. Visual assessment (VA) is widely used to assess Ki67 LI, but has some limitations. In this study, we compared the consistency between VA and automated digital image analysis (DIA) of Ki67 LI in breast cancer, and to evaluate the application value of DIA in Ki67 LI assessment. METHODS Ki67 immunostained slides of 155 cases of primary invasive breast cancer were eyeballing assessed by five breast pathologists and automated digital image analyzed by one breast pathologist respectively. Two score methods, hot-spot score and average score, were used to choose score areas. The intra-class correlation coefficient (ICC) was used to analyze the consistency between VA and DIA, and Wilcoxon signed-rank test was used to compare the median of paired-difference between VA and DIA values. RESULTS (1) A perfect agreement was demonstrated between VA and DIA of Ki67 LI by ICC analysis (P<0.0001) in the whole cohort. A perfect agreement between VA and DIA of Ki67 LI was also showed in G2-G3, ER positive/HER2 negative cases. Average score and hot-spot score methods both demonstrated a perfect concordance between VA and DIA of Ki67 LI. (2) All cases were classified into three groups by VA values (≤10%, 11%-30% and >30% Ki67 LI). The concordance was relatively lower in intermediate Ki67 LI group (11%-30%) compared with high (>30%) Ki67 LI groups according to both methods. (3) All cases were classified into three groups by paired-difference (d) between VA values of hot-spot score and average score (d<5, 5≤d<10, d≥10) to evaluate the correlation between Ki67 staining distribution (heterogeneous or homogenous) and reproducibility of assessment. A perfect agreement was all demonstrated in three groups, and a slightly better Ki67 LI agreement between VA and DIA was indicated in homogenous staining slides than in heterogeneous staining ones. (4) VA values were relatively smaller than DIA values (average score: median of paired-difference -3.72; hot-spot score: median of paired-difference -9.12). CONCLUSIONS An excellent agreement between VA and DIA of Ki67 LI in breast cancer was demonstrated in the whole mixed cohort, suggesting that VA and DIA both could be used to assess Ki67 LI in clinical practice. Average score and hot-spot score methods both demonstrated a perfect concordance between VA and DIA of Ki67 LI. The almost perfect agreement between VA and DIA was observed in high Ki67 LI cases, displaying a homogenous staining pattern. The consistency between VA and DIA was relatively low in intermediate Ki67 LI group. The heterogeneity of tumors may slightly affect the concordance between VA and DIA of Ki67 LI. Assessment of VA provides lower Ki67 values than DIA, the biological importance of these values are not known at the moment.
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Affiliation(s)
- Fangfang Zhong
- Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Rui Bi
- Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Baohua Yu
- Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Fei Yang
- Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wentao Yang
- Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Ruohong Shui
- Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
- * E-mail:
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13
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Xiang QM, Wang LW, Yuan JP, Chen JM, Yang F, Li Y. Quantum dot-based multispectral fluorescent imaging to quantitatively study co-expressions of Ki67 and HER2 in breast cancer. Exp Mol Pathol 2015; 99:133-8. [PMID: 26102249 DOI: 10.1016/j.yexmp.2015.06.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 06/18/2015] [Indexed: 12/13/2022]
Abstract
Both Ki67 and HER2 are key prognostic molecules for invasive breast cancer (BC), but the individual relative impacts on prognosis of these molecules are not known. This study was aimed at establishing a quantum dot (QD)-based double-color in-situ quantitative imaging technique to study the co-expressions of Ki67 and HER2, and delineate the individual impacts of these molecules on prognosis. The QD-based fluorescent immunostaining technique could simultaneously image the co-expressions of Ki67 and HER2 in BC specimens, with the former stained as clear red fluorescence in cancer cell nucleus, and the latter as bright green fluorescence on cancer cell membrane. Both Ki67 and HER2 expressions were significantly correlated with 8-year disease free survival (8-DFS) (P<0.05). However, the two molecules had different weights in terms of negative impacts on clinical prognosis. The median 8-DFS was statistically significantly shorter in High-Ki67 High-HER2 subgroup than Low-Ki67 High-HER2 subgroup (11.7 vs. 60.1months, P<0.05), shorter in High-Ki67 Low-HER2 subgroup than Low-Ki67 Low-HER2 subgroup (16.4 vs. 96.0months, P<0.01), shorter in High-Ki67 High-HER2 subgroup than Low-Ki67 Low-HER2 subgroup (11.7 vs. 96.0months, P<0.01), but there were no statistically significant differences in median 8-DFS between High-Ki67 Low-HER2 subgroup and High-Ki67 High-HER2 subgroup (11.7 vs. 16.4months, P=0.586). The hazard ratio (HR) of Ki67 negative impact on 8-DFS was about 3 fold of that of HER2 (HR 4.493 vs. 1.481). This study demonstrated that QD-based fluorescent imaging technique could help the quantitative study on the co-expressions of Ki67 and HER2 in BC, and Ki67 has a greater negative impact on BC prognosis than HER2.
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Affiliation(s)
- Qing-Ming Xiang
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan City, Hubei Province, China
| | - Lin-Wei Wang
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan City, Hubei Province, China
| | - Jing-Ping Yuan
- Department of Pathology, Renmin Hospital of Wuhan University, Wuhan City, Hubei Province, China
| | - Jia-Mei Chen
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan City, Hubei Province, China
| | - Fang Yang
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan City, Hubei Province, China
| | - Yan Li
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan City, Hubei Province, China.
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14
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Shui R, Yu B, Bi R, Yang F, Yang W. An interobserver reproducibility analysis of Ki67 visual assessment in breast cancer. PLoS One 2015; 10:e0125131. [PMID: 25932921 PMCID: PMC4416820 DOI: 10.1371/journal.pone.0125131] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 03/11/2015] [Indexed: 12/20/2022] Open
Abstract
Background Ki67 labeling index (LI) is used as a predictive marker and is associated with prognosis in breast cancer. However, standardised methodologies for measurement are lacking which has limited its application in clinical practice. In this study, we evaluated the interobserver concordance of visual assessment of Ki67 LI in breast cancer. Methods Ki67- immunostained slides of 160 cases of primary invasive breast cancer were visual assessed by five breast pathologists with two different methods to choose the scoring fields: (1) hot-spot score, (2) average score. Proportions of positive invasive tumor cells at 10 % intervals were scored. The intra-class correlation coefficient (ICC) was used to assess the interobserver reproducibility. Results (1) A perfect concordance of Ki67 LI was demonstrated according to both score methods (P<0.0001). Average score method (ICC, 0.904) demonstrated a better correlation than hot-spot score method (ICC, 0.894). (2) By respective means according to two score methods, all cases were classified into three groups (≤10%, 11%-30% and >30% Ki-67 LI). The concordance was relatively low in intermediate Ki67 LI group compared with low and high Ki67 LI groups. (3) All cases were classified into three groups by paired-difference (d) between means of hot-spot score and average score (d<5, 5≤d<10, d≥10). The consistency was observed to decrease with increasing paired-difference according to both methods. Conclusions Visual assessment of Ki67 LI at 10 % intervals is a candidate for a standard method in breast cancer clinical practice. Average score and hot-spot score of visual assessment both demonstrated a perfect concordance, and an overall average assessment across the whole section including hot spots may be a better method. Interobserver concordance of intermediate Ki67 LI in which most cutoffs are located for making clinical decisions was relatively low.
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Affiliation(s)
- Ruohong Shui
- Department of Pathology, Fudan University Shanghai Cancer Center, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Baohua Yu
- Department of Pathology, Fudan University Shanghai Cancer Center, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Rui Bi
- Department of Pathology, Fudan University Shanghai Cancer Center, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Fei Yang
- Department of Pathology, Fudan University Shanghai Cancer Center, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Wentao Yang
- Department of Pathology, Fudan University Shanghai Cancer Center, Fudan University, Shanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
- * E-mail:
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15
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Yuan JP, Wang LW, Qu AP, Chen JM, Xiang QM, Chen C, Sun SR, Pang DW, Liu J, Li Y. Quantum dots-based quantitative and in situ multiple imaging on ki67 and cytokeratin to improve ki67 assessment in breast cancer. PLoS One 2015; 10:e0122734. [PMID: 25856425 PMCID: PMC4391934 DOI: 10.1371/journal.pone.0122734] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 02/12/2015] [Indexed: 01/16/2023] Open
Abstract
Background As a marker for tumor cell proliferation, Ki67 has important impacts on breast cancer (BC) prognosis. Although immunohistochemical staining is the current standard method, variations in analytical practice make it difficult for pathologists to manually measure Ki67 index. This study was to develop a fluorescent spectrum-based quantitative analysis of Ki67 expression by quantum-dots (QDs) multiple imaging technique. Methods A QDs-based in situ multiple fluorescent imaging method was developed, which stained nuclear Ki67 as red signal and cytoplasmic cytokeratin (CK) as green signal. Both Ki67 and CK signals were automatically separated and quantified by professional spectrum analysis software. This technique was applied to tissue microarrays from 240 BC patients. Both Ki67 and CK values, and Ki67/CK ratio were obtained for each patient, and their prognostic value on 5-year disease free survival was assessed. Results This method simultaneously stains nuclear Ki67 and cytoplasmic CK with clear signal contrast, making it easy for signal separation and quantification. The total fluorescent signal intensities of both Ki67 sum and CK sum were obtained, and Ki67/CK ratio calculated. Ki67 sum and Ki67/CK ratio were each attributed into two grades by X-tile software based on the best P value principle. Multivariate analysis showed Ki67 grade (P = 0.047) and Ki67/CK grade (P = 0.004) were independent prognostic factors. Furthermore, area under curve (AUC) of ROC analysis for Ki67/CK grade (AUC: 0.683, 95%CI: 0.613–0.752) was higher than Ki67 grade (AUC: 0.665, 95%CI: 0.596–0.734) and HER-2 gene (AUC: 0.586, 95%CI: 0.510–0.661), but lower than N stage (AUC: 0.760, 95%CI: 0.696–0.823) and histological grade (AUC: 0.756, 95%CI: 0.692–0.820) on predicting the risk for recurrence. Conclusions A QDs-based quantitative and in situ multiple imaging on Ki67 and CK was developed to improve Ki67 assessment in BC, and Ki67/CK grade had better performance than Ki67 grade in predicting prognosis.
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Affiliation(s)
- Jing Ping Yuan
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan, Hubei, China
| | - Lin Wei Wang
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan, Hubei, China
| | - Ai Ping Qu
- School of Computer, Wuhan University, Wuhan, Hubei, China
| | - Jia Mei Chen
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan, Hubei, China
| | - Qing Ming Xiang
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan, Hubei, China
| | - Chuang Chen
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Sheng-Rong Sun
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Dai-Wen Pang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, and Wuhan Institute of Biotechnology, Wuhan University, Wuhan, Hubei, China
| | - Juan Liu
- School of Computer, Wuhan University, Wuhan, Hubei, China
| | - Yan Li
- Department of Oncology, Zhongnan Hospital of Wuhan University, Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, Wuhan, Hubei, China
- * E-mail:
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16
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de Gramont A, Watson S, Ellis LM, Rodón J, Tabernero J, de Gramont A, Hamilton SR. Pragmatic issues in biomarker evaluation for targeted therapies in cancer. Nat Rev Clin Oncol 2014; 12:197-212. [PMID: 25421275 DOI: 10.1038/nrclinonc.2014.202] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Predictive biomarkers are becoming increasingly important tools in drug development and clinical research. The importance of using both guidelines for specimen acquisition and analytical methods for biomarker measurements that are standardized has become recognized widely as an important issue, which must be addressed in order to provide high-quality, validated assays. Herein, we review the major challenges in biomarker validation processes, including pre-analytical (sample-related), analytical, and post-analytical (data-related) aspects of assay development. Recommendations for improving biomarker assay development and method validation are proposed to facilitate the use of predictive biomarkers in clinical trials and the practice of oncology.
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Affiliation(s)
- Armand de Gramont
- New Drug Evaluation Laboratory, Centre of Experimental Therapeutics, Department of Oncology, Centre Hospitalier Universitaire Vaudois (CHUV), 1011 Lausanne, Switzerland
| | - Sarah Watson
- INSERM U830, Genetics and Biology of Paediatric Tumours Group, Institut Curie, France
| | - Lee M Ellis
- Departments of Surgical Oncology, and Molecular and Cellular Oncology, University of Texas MD Anderson Cancer Center, USA
| | - Jordi Rodón
- Medical Oncology, Vall d'Hebron University Hospital, Vall d'Hebron Institute of Oncology (VHIO) and Universitat Autonoma de Barcelona (UAB), Spain
| | - Josep Tabernero
- Medical Oncology, Vall d'Hebron University Hospital, Vall d'Hebron Institute of Oncology (VHIO) and Universitat Autonoma de Barcelona (UAB), Spain
| | - Aimery de Gramont
- Medical Oncology Department, Institut Hospitalier Franco-Britannique, France
| | - Stanley R Hamilton
- Division of Pathology and Laboratory Medicine, University of Texas MD Anderson Cancer Center, USA
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17
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Kalkman S, Bulte JP, Halilovic A, Bult P, van Diest PJ. Brief fixation does not hamper the reliability of Ki67 analysis in breast cancer core-needle biopsies: a double-centre study. Histopathology 2014; 66:380-7. [PMID: 25234295 DOI: 10.1111/his.12521] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 08/03/2014] [Indexed: 12/20/2022]
Abstract
AIMS Immunohistochemical assessment of Ki67 expression in core-needle biopsies (CNBs) is increasingly playing a role in therapeutic decision-making for breast cancer patients. Within the framework of same-day diagnosis of breast lesions, fixation times are markedly decreased. We therefore attempted to validate Ki67 analysis in briefly fixed breast cancer CNBs. METHODS AND RESULTS CNBs of 136 consecutive patients with invasive breast cancer diagnosed through the same-day diagnosis programme of both the University Medical Centre Utrecht (UMCU) and the Radboud University Medical Centre (RUMC) were included. CNBs were fixed in formaldehyde for approximately 45 min at the UMCU and for between 60 and 90 min at the RUMC. Immunohistochemistry for Ki67 expression was compared between the briefly fixed CNBs and conventionally fixed resection specimens of the same tumour. The overall agreement between CNBs and resections was 122 of 142 (85.9%) (κ = 0.71; 95% CI 0.60-0.83). Positive and negative predictive values were 79.7% (95% CI 67-88%) and 91.0% (95% CI 82-96%), respectively. CONCLUSIONS Overall agreement for Ki67 expression was good between briefly fixed CNBs and conventionally fixed resection specimens, and within the range of studies comparing conventionally fixed CNBs and resections.
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Affiliation(s)
- Shona Kalkman
- Department of Pathology, University Medical Centre Utrecht, Utrecht, The Netherlands
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18
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Different methods of pretreatment Ki-67 labeling index evaluation in core biopsies of breast cancer patients treated with neoadjuvant chemotherapy and their relation to response to therapy. Pathol Oncol Res 2014; 21:147-55. [PMID: 24859973 DOI: 10.1007/s12253-014-9800-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 05/16/2014] [Indexed: 12/30/2022]
Abstract
Increased proliferation activity of breast cancer cells evaluated by Ki-67 immunohistochemistry, i.e. a high Ki-67 labeling index (Ki-67 LI), may predict better tumor regression in case of neoadjuvant chemotherapy. Despite recommendations for the evaluation of Ki-67 LI, there are variations in methodology. We assessed the effect of different evaluation methods on the Ki-67 LI in patients with different response to neoadjuvant chemotherapy. Thirty pretreatment core-biopsy samples of patients receiving neoadjuvant docetaxel-epirubicin chemotherapy with or without capecitabine were evaluated for their Ki-67 LI. Pathologic regression was categorized as no regression, partial regression and complete regression, with 10 cases in each category. Three antibodies (MIB1, B56, SP6), 4 observers and 4 methods (counting or estimating on glass slides and counting or estimating on representative digital images) were compared. The Kruskal-Wallis test and analyses of variance were performed to investigate the differences in Ki-67 LIs between different clinical outcomes (tumor regression categories). Breast carcinomas with pathological complete regression had a higher mean Ki-67 LI than tumors not achieving complete regression with any methods, observers and antibodies investigated, although there was a variation between different evaluations in what may represent high proliferation. Estimating the Ki-67 LI on digital images representing the highest proliferation in the core biopsy seemed the best in separating complete responders from non-responders. High Ki-67 LI values were more likely associated with pathological complete regression independently of the method of evaluation used, although the definition of high proliferation is problematic. Estimating the Ki-67 LI may be an adequate method of evaluation.
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19
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Ekholm M, Beglerbegovic S, Grabau D, Lövgren K, Malmström P, Hartman L, Fernö M. Immunohistochemical assessment of Ki67 with antibodies SP6 and MIB1 in primary breast cancer: a comparison of prognostic value and reproducibility. Histopathology 2014; 65:252-60. [PMID: 24527721 DOI: 10.1111/his.12392] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Accepted: 02/10/2014] [Indexed: 12/23/2022]
Abstract
AIMS To compare SP6 and MIB1 antibodies for assessment of Ki67 in primary breast cancer with regard to prognostic value and reproducibility. METHODS AND RESULTS A cohort of 237 premenopausal women with node-negative breast cancer, mainly (87%) not treated with adjuvant systemic therapy, was used. Assessment of Ki67 (SP6 and MIB1) was performed on tissue microarray by three different investigators. The seventh decile was applied for cut-off. Distant disease-free survival (DDFS) was chosen as endpoint and the follow-up was restricted to 5 years. Eighty-nine per cent of the samples were classified into the same proliferation group, irrespective of antibody used. For both antibodies, high Ki67 was associated with inferior DDFS in univariable analyses (SP6: HR 2.5, P = 0.01; and MIB1: HR 2.8, P = 0.004), but failed to reach statistical significance for DDFS in multivariable analyses adjusted for HER2, age, and tumour size (SP6: HR 2.0, P = 0.074; and MIB1: HR 2.2, P = 0.058). The agreement between different assessors was somewhat higher for MIB1 than for SP6 (κ 0.83-0.88 versus 0.72-0.77). CONCLUSIONS SP6 was not superior to MIB1, but the two antibodies were comparable in the assessment of Ki67. Both MIB1 and SP6 could therefore be considered for prognostic use in primary breast cancer.
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Affiliation(s)
- Maria Ekholm
- Department of Oncology, Ryhov County Hospital, Jönköping, Sweden; Division of Oncology and Pathology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
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20
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Cserni G, Vörös A, Liepniece-Karele I, Bianchi S, Vezzosi V, Grabau D, Sapino A, Castellano I, Regitnig P, Foschini MP, Zolota V, Varga Z, Figueiredo P, Decker T, Focke C, Kulka J, Kaya H, Reiner-Concin A, Amendoeira I, Callagy G, Caffrey E, Wesseling J, Wells C. Distribution pattern of the Ki67 labelling index in breast cancer and its implications for choosing cut-off values. Breast 2014; 23:259-63. [PMID: 24613255 DOI: 10.1016/j.breast.2014.02.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 01/13/2014] [Accepted: 02/14/2014] [Indexed: 01/08/2023] Open
Abstract
The Ki67 labelling index (LI - proportion of staining cells) is widely used to reflect proliferation in breast carcinomas. Several cut-off values have been suggested to distinguish between tumours with low and high proliferative activity. The aim of the current study was to evaluate the distribution of Ki67 LIs in breast carcinomas diagnosed at different institutions by different pathologists using the method reflecting their daily practice. Pathologists using Ki67 were asked to provide data (including the LI, type of the specimen, receptor status, grade) on 100 consecutively stained cases, as well as details of their evaluation. A full dataset of 1709 carcinomas was collected from 19 departments. The median Ki67 LI was 17% for all tumours and 14% for oestrogen receptor-positive and HER2-negative carcinomas. Tumours with higher mitotic counts were associated with higher Ki67 LIs. Ki67 LIs tended to cluster around values ending with 5 or 0 both in cases where the values were obtained by counting the proportion of stained tumour cell nuclei and those where the values were obtained by estimation. On the basis of the distribution pattern described, some currently used Ki67 LI cut off values are not realistic, and it is proposed to select more realistic values ending with 0 or 5.
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Affiliation(s)
- Gábor Cserni
- Bács-Kiskun County Teaching Hospital, Kecskemét, Hungary; Department of Pathology, University of Szeged, Hungary.
| | - András Vörös
- Department of Pathology, University of Szeged, Hungary
| | | | - Simonetta Bianchi
- Section of Pathological Anatomy, Department of Surgery and Translational Medicine, University of Florence, AOU Careggi, Largo GA Brambilla 3, 50134 Florence, Italy
| | - Vania Vezzosi
- Section of Pathological Anatomy, Department of Surgery and Translational Medicine, University of Florence, AOU Careggi, Largo GA Brambilla 3, 50134 Florence, Italy
| | - Dorthe Grabau
- Department of Pathology, Skåne University Hospital, Lund, Sweden
| | - Anna Sapino
- Department of Medical Sciences, University of Turin, Italy
| | | | - Peter Regitnig
- Medical University of Graz, Institute of Pathology, Auenbruggerplatz 25, A-8036 Graz, Austria
| | - Maria Pia Foschini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Anatomic Pathology at Bellaria Hospital, Via Altura, 3, 40139 Bologna, Italy
| | - Vassiliki Zolota
- Department of Pathology, Medical School, University of Patras, Rion, Patras, Greece
| | - Zsuzsanna Varga
- Institute of Surgical Pathology, University Hospital Zurich, Zurich, Switzerland
| | - Paulo Figueiredo
- Lab Histopatologia, Av Bissaya Barreto, Apartado 2005, 3001-651 Coimbra, Portugal
| | - Thomas Decker
- Department of Pathology, Dietrich Bonhoeffer Medical Centre, Allendestraße 30, D-17036 Neubrandenburg, Germany
| | - Cornelia Focke
- Department of Pathology, Dietrich Bonhoeffer Medical Centre, Allendestraße 30, D-17036 Neubrandenburg, Germany
| | - Janina Kulka
- 2nd Department of Pathology, Semmelweis University Budapest, Üllői út 93, H-1091 Budapest, Hungary
| | - Handan Kaya
- Marmara University School of Medicine, Department of Pathology, Istanbul, Turkey
| | | | - Isabel Amendoeira
- Department of Pathology, Centro Hospitalar de S. João and Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Portugal
| | - Grace Callagy
- Discipline of Pathology, NUI Galway, Galway, Ireland
| | - Emer Caffrey
- Discipline of Pathology, NUI Galway, Galway, Ireland
| | - Jelle Wesseling
- Department of Pathology, Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands; Department of Molecular Pathology, Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Clive Wells
- Department of Pathology, University College Hospital, London, United Kingdom
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21
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Dietel M, Heppner BI. E11. Quality assurance and breast cancer pathology. Eur J Cancer 2014. [DOI: 10.1016/s0959-8049(14)70063-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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22
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Stålhammar G, Rosin G, Fredriksson I, Bergh J, Hartman J. Low concordance of biomarkers in histopathological and cytological material from breast cancer. Histopathology 2014; 64:971-80. [PMID: 24320941 DOI: 10.1111/his.12344] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 12/04/2013] [Indexed: 12/11/2022]
Abstract
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.
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Affiliation(s)
- Gustav Stålhammar
- Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden; Department of Clinical Pathology, Karolinska University Hospital, Stockholm, Sweden
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Quantitative assessment Ki-67 score for prediction of response to neoadjuvant chemotherapy in breast cancer. J Transl Med 2014; 94:98-106. [PMID: 24189270 DOI: 10.1038/labinvest.2013.128] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 10/02/2013] [Accepted: 10/04/2013] [Indexed: 12/20/2022] Open
Abstract
Measurement of Ki-67, a marker of cell proliferation, has been associated with response to therapy, but methods of measurement are controversial. Here we use a quantitative objective measurement for Ki-67 to determine the best method for assessment of Ki-67 for prediction of response to neoadjuvant chemotherapy. Analysis was conducted on a cohort of 105 consecutive invasive breast cancer patients that received neoadjuvant therapy between 2002 and 2010, and on whom pre-surgical biopsies were obtainable. Ki-67 expression was measured using quantitative immunofluorescence automated quantitative analysis (AQUA) technology. Images for each specimen were collected for 5 to 115 fields of view (FOVs) and summary scores were obtained, corresponding to the average and maximum of all the FOVs. AQUA scoring (using both intensity and area) was comparable to automated calculation of percentage of positive nuclei for prediction of response to chemotherapy (OR: 2.832 vs 2.712). Both the average and maximum AQUA score showed Ki-67 expression was directly correlated to pathological complete response (pCR; average P=0.0002; maximum P=0.0011). Although examining the maximum FOV was more predictive of response to therapy (OR: 3.546 vs 2.832), averaging all fields provided more sensitivity and specificity (AUC 0.769 vs 0.732). Ki-67 average (P=0.0025) and maximum (P=0.0239) AQUA score were also significant predictors of pCR in a multivariable analysis, including tumor size, nuclear grade, nodal status, ER status, and HER2 status. Measurement of Ki-67 expression by objective quantitative methods shows increased Ki-67 levels are an independent predictor of response to neoadjuvant chemotherapy.
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The use of digital images improves reproducibility of the ki-67 labeling index as a proliferation marker in breast cancer. Pathol Oncol Res 2013; 20:391-7. [PMID: 24202856 DOI: 10.1007/s12253-013-9708-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 10/02/2013] [Indexed: 02/07/2023]
Abstract
The proportion of Ki-67 immunostained cells (Ki-67 labeling index, LI) is one of the most commonly used histology methods for estimating proliferation of breast carcinomas. Although the Ki-67 LI is used in treatment decision making, its reproducibility shows variation in different studies, and is generally less then optimal. The aim of the present study was to investigate how the use of a standardized, partially digitalized counting method could affect reproducibility of determining the Ki-67 LI. Thirty breast cancer core-biopsy samples were stained with B-56, SP-6 and MIB-1 monoclonal Ki-67 antibodies. Each sample was represented by a single digital photograph taken with a x20 objective. Four investigators determined the Ki-67 LI on these digital images by estimation, then by counting with the help of a grid overlaid on the same images. Altogether 720 evaluations were made by 4 independent pathologists. Good to excellent correlation was found between estimations and calculations of each observer. Kappa values >0.6 suggest substantial inter-observer agreement when classifying the cases into a 15 % and 30 % cut-off determined three-tiered or a 4-quarter-based four-tiered categorization, which is better than the fair reproducibility gained on the real slides in a previous study. The results also suggest that the type of the antibody may also impact on the consistency of both estimating and calculating the Ki-67 LIs. The results indicate that counting on digital images may significantly improve reproducibility of determining the KI-67 LI. Interestingly, estimation on the same images is not worse, but is obviously faster and more convenient.
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