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Annals of Oncology | 2015

The evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer: recommendations by an International TILs Working Group 2014

Roberto Salgado; Carsten Denkert; Sandra Demaria; Nicolas Sirtaine; Frederick Klauschen; Giancarlo Pruneri; Stephan Wienert; G. Van den Eynden; F. L. Baehner; Frédérique Penault-Llorca; Edith A. Perez; E. A. Thompson; W. F. Symmans; Andrea L. Richardson; Jane E. Brock; Carmen Criscitiello; H. Bailey; Michail Ignatiadis; G. Floris; Joseph A. Sparano; Zuzana Kos; Torsten O. Nielsen; David L. Rimm; Kimberly H. Allison; Jorge S. Reis-Filho; Sibylle Loibl; Christos Sotiriou; Giuseppe Viale; Sunil Badve; Sylvia Adams

BACKGROUND The morphological evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer (BC) is gaining momentum as evidence strengthens for the clinical relevance of this immunological biomarker. Accumulating evidence suggests that the extent of lymphocytic infiltration in tumor tissue can be assessed as a major parameter by evaluation of hematoxylin and eosin (H&E)-stained tumor sections. TILs have been shown to provide prognostic and potentially predictive value, particularly in triple-negative and human epidermal growth factor receptor 2-overexpressing BC. DESIGN A standardized methodology for evaluating TILs is now needed as a prerequisite for integrating this parameter in standard histopathological practice, in a research setting as well as in clinical trials. This article reviews current data on the clinical validity and utility of TILs in BC in an effort to foster better knowledge and insight in this rapidly evolving field, and to develop a standardized methodology for visual assessment on H&E sections, acknowledging the future potential of molecular/multiplexed approaches. CONCLUSIONS The methodology provided is sufficiently detailed to offer a uniformly applied, pragmatic starting point and improve consistency and reproducibility in the measurement of TILs for future studies.


Breast Cancer Research | 2014

Prognostic significance of FOXP3+ tumor-infiltrating lymphocytes in breast cancer depends on estrogen receptor and human epidermal growth factor receptor-2 expression status and concurrent cytotoxic T-cell infiltration

Shuzhen Liu; William D. Foulkes; Samuel Leung; Dongxia Gao; Sherman Lau; Zuzana Kos; Torsten O. Nielsen

IntroductionThe infiltration of FOXP3+ regulatory T cells into invasive tumors has been reported to be associated with survival in a variety of cancers. The prognostic significance of FOXP3+ tumor-infiltrating lymphocytes (TILs) in breast cancer, however, remains controversial.MethodsFOXP3+ TILs were assessed by immunohistochemistry on tissue microarrays constructed from a well-defined cohort of 3,992 breast cancer patients linked to detailed demographic, biomarker, treatment and outcome data. Survival analyses were performed using the Kaplan-Meier function and Cox proportional hazards regression models to evaluate the association of FOXP3+ TILs with breast cancer-specific survival, stratified by intrinsic subtype and cytotoxic T-cell infiltration status (as defined by CD8 immunohistochemistry).ResultsThe presence of high numbers of FOXP3+ TILs was significantly associated with young age, high grade, estrogen receptor (ER) negativity, concurrent CD8+ cytotoxic T-cell infiltration, and human epidermal growth factor receptor-2 positive (HER2+)/ER+ and core basal subtypes. On multivariate survival analysis, a high level of FOXP3+ TILs was significantly associated with poor survival in ER+ breast cancers that lacked CD8+ T-cell infiltrates (hazard ratio (HR) = 1.30, 95% confidence interval (CI) = 1.02 to 1.66). However, in ER+ breast cancers, FOXP3+ TILs were strongly associated with improved survival in the HER2+/ER+ subgroup, particularly in those with co-existent CD8+ T-cell infiltrates (HR = 0.48, 95% CI = 0.23 to 0.98), for which the presence of high levels of FOXP3+ TILs was independent of standard clinical prognostic factors.ConclusionsFOXP3+ regulatory TILs are a poor prognostic indicator in ER+ breast cancer, but a favorable prognostic factor in the HER2+/ER+ subtype. The prognostic value of FOXP3+ TILs in breast cancer differs depending on ER and HER2 expression status and CD8+ T-cell infiltration.


Modern Pathology | 2016

Standardized evaluation of tumor-infiltrating lymphocytes in breast cancer : results of the ring studies of the international immuno-oncology biomarker working group

Carsten Denkert; Stephan Wienert; Audrey Poterie; Sibylle Loibl; Jan Budczies; Sunil Badve; Zsuzsanna Bago-Horvath; Anita Bane; Shahinaz Bedri; Jane E. Brock; Ewa Chmielik; Matthias Christgen; Cecile Colpaert; Sandra Demaria; Gert Van den Eynden; Giuseppe Floris; Stephen B. Fox; Dongxia Gao; Barbara Ingold Heppner; S Rim Kim; Zuzana Kos; Hans Kreipe; Sunil R. Lakhani; Frédérique Penault-Llorca; Giancarlo Pruneri; Nina Radosevic-Robin; David L. Rimm; Stuart J. Schnitt; Bruno V. Sinn; Peter Sinn

Multiple independent studies have shown that tumor-infiltrating lymphocytes (TIL) are prognostic in breast cancer with potential relevance for response to immune-checkpoint inhibitor therapy. Although many groups are currently evaluating TIL, there is no standardized system for diagnostic applications. This study reports the results of two ring studies investigating TIL conducted by the International Working Group on Immuno-oncology Biomarkers. The study aim was to determine the intraclass correlation coefficient (ICC) for evaluation of TIL by different pathologists. A total of 120 slides were evaluated by a large group of pathologists with a web-based system in ring study 1 and a more advanced software-system in ring study 2 that included an integrated feedback with standardized reference images. The predefined aim for successful ring studies 1 and 2 was an ICC above 0.7 (lower limit of 95% confidence interval (CI)). In ring study 1 the prespecified endpoint was not reached (ICC: 0.70; 95% CI: 0.62–0.78). On the basis of an analysis of sources of variation, we developed a more advanced digital image evaluation system for ring study 2, which improved the ICC to 0.89 (95% CI: 0.85–0.92). The Fleiss’ kappa value for <60 vs ≥60% TIL improved from 0.45 (ring study 1) to 0.63 in RS2 and the mean concordance improved from 88 to 92%. This large international standardization project shows that reproducible evaluation of TIL is feasible in breast cancer. This opens the way for standardized reporting of tumor immunological parameters in clinical studies and diagnostic practice. The software-guided image evaluation approach used in ring study 2 may be of value as a tool for evaluation of TIL in clinical trials and diagnostic practice. The experience gained from this approach might be applicable to the standardization of other diagnostic parameters in histopathology.


Advances in Anatomic Pathology | 2017

Assessing tumor-infiltrating lymphocytes in solid tumors: a practical review for pathologists and proposal for a standardized method from the International Immuno-Oncology Biomarkers Working Group: part 2: TILs in melanoma, gastrointestinal tract carcinomas, non-small cell lung carcinoma and mesothelioma, endometrial and ovarian carcinomas, squamous cell carcinoma of the head and neck, genitourinary carcinomas, and primary brain Tumors

Shona Hendry; Roberto Salgado; Thomas Gevaert; Prudence A. Russell; Thomas John; Bibhusal Thapa; Michael Christie; Koen K. Van de Vijver; Monica V. Estrada; Paula I Gonzalez-Ericsson; Melinda E. Sanders; Benjamin Solomon; Cinzia Solinas; Gert G. Van den Eynden; Yves Allory; Matthias Preusser; Johannes A. Hainfellner; Giancarlo Pruneri; Andrea Vingiani; Sandra Demaria; Fraser Symmans; Paolo Nuciforo; Laura Comerma; E. A. Thompson; Sunil R. Lakhani; Seong Rim Kim; Stuart J. Schnitt; Cecile Colpaert; Christos Sotiriou; Stefan J. Scherer

Assessment of the immune response to tumors is growing in importance as the prognostic implications of this response are increasingly recognized, and as immunotherapies are evaluated and implemented in different tumor types. However, many different approaches can be used to assess and describe the immune response, which limits efforts at implementation as a routine clinical biomarker. In part 1 of this review, we have proposed a standardized methodology to assess tumor-infiltrating lymphocytes (TILs) in solid tumors, based on the International Immuno-Oncology Biomarkers Working Group guidelines for invasive breast carcinoma. In part 2 of this review, we discuss the available evidence for the prognostic and predictive value of TILs in common solid tumors, including carcinomas of the lung, gastrointestinal tract, genitourinary system, gynecologic system, and head and neck, as well as primary brain tumors, mesothelioma and melanoma. The particularities and different emphases in TIL assessment in different tumor types are discussed. The standardized methodology we propose can be adapted to different tumor types and may be used as a standard against which other approaches can be compared. Standardization of TIL assessment will help clinicians, researchers and pathologists to conclusively evaluate the utility of this simple biomarker in the current era of immunotherapy.


npj Breast Cancer | 2016

Analytical validation of a standardized scoring protocol for Ki67: phase 3 of an international multicenter collaboration

Samuel C. Y. Leung; Torsten O. Nielsen; Lila Zabaglo; Indu Arun; Sunil Badve; Anita Bane; John M.S. Bartlett; Signe Borgquist; Martin C. Chang; Andrew Dodson; Rebecca A. Enos; Susan Fineberg; Cm Focke; Dongxia Gao; Allen M. Gown; Dorthe Grabau; Carolina Gutierrez; Judith Hugh; Zuzana Kos; Anne-Vibeke Laenkholm; Ming-Gang Lin; Mauro G. Mastropasqua; Takuya Moriya; Sharon Nofech-Mozes; C. Kent Osborne; Frédérique Penault-Llorca; Tammy Piper; Takashi Sakatani; Roberto Salgado; Jane Starczynski

Pathological analysis of the nuclear proliferation biomarker Ki67 has multiple potential roles in breast and other cancers. However, clinical utility of the immunohistochemical (IHC) assay for Ki67 immunohistochemistry has been hampered by unacceptable between-laboratory analytical variability. The International Ki67 Working Group has conducted a series of studies aiming to decrease this variability and improve the evaluation of Ki67. This study tries to assess whether acceptable performance can be achieved on prestained core-cut biopsies using a standardized scoring method. Sections from 30 primary ER+ breast cancer core biopsies were centrally stained for Ki67 and circulated among 22 laboratories in 11 countries. Each laboratory scored Ki67 using three methods: (1) global (4 fields of 100 cells each); (2) weighted global (same as global but weighted by estimated percentages of total area); and (3) hot-spot (single field of 500 cells). The intraclass correlation coefficient (ICC), a measure of interlaboratory agreement, for the unweighted global method (0.87; 95% credible interval (CI): 0.81–0.93) met the prespecified success criterion for scoring reproducibility, whereas that for the weighted global (0.87; 95% CI: 0.7999–0.93) and hot-spot methods (0.84; 95% CI: 0.77–0.92) marginally failed to do so. The unweighted global assessment of Ki67 IHC analysis on core biopsies met the prespecified criterion of success for scoring reproducibility. A few cases still showed large scoring discrepancies. Establishment of external quality assessment schemes is likely to improve the agreement between laboratories further. Additional evaluations are needed to assess staining variability and clinical validity in appropriate cohorts of samples.


Histopathology | 2016

Biomarker assessment and molecular testing for prognostication in breast cancer.

Zuzana Kos; David J. Dabbs

Current treatment of breast cancer incorporates clinical, pathological and molecular data. Oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) define prognosis and identify tumours for targeted therapy, and remain the sole established single‐molecule biomarkers defining the minimum breast cancer pathology data set. Ki67 remains one of the most promising yet controversial biomarkers in breast cancer, implemented routinely in some, but not all, pathology departments. Beyond the single‐molecule biomarkers, a host of multigene expression tests have been developed to interrogate the driver pathways and biology of individual breast cancers to predict clinical outcome more accurately. A minority of these assays have entered into clinical practice. This review focuses on the established biomarkers of ER, PR and HER2, the controversial but clinically implemented biomarker Ki67 and the currently marketed gene expression signatures.


International Journal of Surgical Pathology | 2014

A Rare Case of Anaplastic Variant of Diffuse Large B-Cell Lymphoma Presenting as a Lung Primary

Zuzana Kos; Bruce F. Burns; Marcio M. Gomes; Harmanjatinder S. Sekhon

Primary pulmonary lymphoma is an uncommon neoplastic disorder representing approximately 0.5% to 1% of primary pulmonary malignancies. The vast majority are of low-grade, mucosa-associated lymphoid tissue type. Primary diffuse large B-cell lymphoma of the lung is rare, though cases of the centroblastic and immunoblastic variants have been described. We present herein an interesting case of an 80-year-old man who presented with both respiratory and constitutional symptoms and was found to have a 4.5 cm left hilar mass with bilateral hilar and mediastinal lymphadenopathy on imaging. Endobronchial biopsy revealed an aggressive large cell lymphoma, with scattered large, bizarre-shaped nuclei resembling Reed–Sternberg cells, positive for CD20, PAX5, CD30, and MUM-1, consistent with an anaplastic variant of diffuse large B-cell lymphoma. Imaging showed no evidence of extrathoracic disease. Standard treatment with cyclophosphamide/vincristine/prednisone and rituximab resulted in significant clinical and radiological response and the patient remains in remission 21 months later. To the best of our knowledge, this modified Ann Arbor stage II2E primary pulmonary lymphoma, is the first description in the English literature of anaplastic variant of diffuse large B-cell lymphoma presenting as a lung primary.


Diagnostic Cytopathology | 2014

Fluorescence in situ hybridization as an adjunct tool in the diagnosis of primary and metastatic renal cell carcinoma in fine needle aspiration specimens

Zuzana Kos; Phillip Williams; Eric C. Belanger; Kien T. Mai

We investigated the role of fluorescence in situ hybridization (FISH) in the diagnosis of primary renal neoplasms and lesions suspicious for metastatic renal cell carcinoma.


Diagnostic Cytopathology | 2014

Three‐dimensional cell groups with disordered nuclei and cellular discohesion (3DDD) are associated with high sensitivity and specificity for cystoscopic urine cytopathological diagnosis of low‐grade urothelial neoplasia

Kien T. Mai; Christopher G. Ball; Zuzana Kos; Eric C. Belanger; Shahidul Islam; Harman S. Sekhon

Cystoscopic urine obtained before the resection of low‐grade urothelial carcinoma (LGUC), with adequate cytological sampling of the tumor, frequently revealed the presence of three‐dimensional cell groups with disordered nuclei and cellular discohesion (3DDD). 936 cystoscopic urine specimens were categorized into five groups: Group 1 (80 specimens) with biopsy‐proven LGUC within 6 months of cytologic examination, Group 2 (23 specimens) with biopsy proven LGUC within 6 to 36 months of cytologic examination, Group 3 (527 specimens) with a history of LGUC but no tumor for a period of greater than 3 years, Group 4 (300 specimens) with no association with LGUC, and Group 5 (6 specimens) with urinary lithiasis. Specimens with scant cellularity accounted for 20% of those in Group 1. For 3DDD in detecting LGUC in adequate cystoscopic urine, the sensitivity was 70%, specificity was 94%. Two‐ or three‐dimensional cell groups with ordered nuclei and/or cellular non‐discohesion were often seen in specimens from Groups 4 or 5. The 3DDD was present in a significant number of cases with concurrent negative cystoscopic findings but also positive LGUC in ensuing follow‐up. In these cases, 3DDD with or without tumor identified at concurrent cystoscopy were found to be morphologically similar. Furthermore, the presence of 3DDD in 8% of Group 3 likely represents urothelial dysplasia that is not cystoscopically detectable. The high specificity and sensitivity of 3DDD is demonstrated. These findings are consistent with the decreased cell adhesion and disordered nuclear arrangement of low grade urothelial neoplasia. Diagn. Cytopathol. 2014;42:555–563.


Breast Cancer Research | 2014

Developing a new generation of breast cancer clinical gene expression tests.

Zuzana Kos; Torsten O. Nielsen

When treatment decisions are based purely on clinicopathological factors, many women with estrogen receptor-positive/human epidermal growth factor receptor 2-negative cancers are overtreated. Gene expression profiles are valuable clinical tools that stratify the recurrence risk to identify patients most likely to benefit from adjuvant systemic therapies. Building upon greater understanding of tumor biology and more rigorous approaches to validation (including independent studies with a high level of evidence), several second-generation multigene tests have been developed. In the previous issue, Martin and colleagues report the third clinical validation study for EndoPredict, a distributed assay to assess risk of distant recurrences in estrogen receptor-positive/human epidermal growth factor receptor 2-negative women. The authors confirm the assay’s independent prognostic value in premenopausal and postmenopausal, node-positive women treated with contemporary chemotherapy followed by endocrine therapy. EndoPredict did not, however, predict benefit from adding paclitaxel. Predictive signatures for selecting among chemotherapy regimens remain an area needing further development.

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Torsten O. Nielsen

University of British Columbia

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Dongxia Gao

University of British Columbia

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Roberto Salgado

Université libre de Bruxelles

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Allen M. Gown

University of British Columbia

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