1
|
van der Werf-'t Lam AS, Terlouw D, Tops CM, van Kan MS, van Hest LP, Gille HJP, Duijkers FAM, Wagner A, Eikenboom EL, Letteboer TGW, de Jong MM, Bajwa-Ten Broeke SW, Bleeker FE, Gomez Garcia EB, de Wind N, van Wezel JT, Morreau H, Suerink M, Nielsen M. Discordant Staining Patterns and Microsatellite Results in Tumors of MSH6 Pathogenic Variant Carriers. Mod Pathol 2023; 36:100240. [PMID: 37307877 DOI: 10.1016/j.modpat.2023.100240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 05/05/2023] [Accepted: 06/06/2023] [Indexed: 06/14/2023]
Abstract
Diagnosis of Lynch syndrome (LS) caused by a pathogenic germline MSH6 variant may be complicated by discordant immunohistochemistry (IHC) and/or by a microsatellite stable (MSS) phenotype. This study aimed to identify the various causes of the discordant phenotypes of colorectal cancer (CRC) and endometrial cancer (EC) in MSH6-associated LS. Data were collected from Dutch family cancer clinics. Carriers of a (likely) pathogenic MSH6 variant diagnosed with CRC or EC were categorized based on an microsatellite instability (MSI)/IHC test outcome that might fail to result in a diagnosis of LS (eg, retained staining of all 4 mismatch repair proteins, with or without an MSS phenotype, and other staining patterns). When tumor tissue was available, MSI and/or IHC were repeated. Next-generation sequencing (NGS) was performed in cases with discordant staining patterns. Data were obtained from 360 families with 1763 (obligate) carriers. MSH6 variant carriers with CRC or EC (n = 590) were included, consisting of 418 CRCs and 232 ECs. Discordant staining was reported in 77 cases (36% of MSI/IHC results). Twelve patients gave informed consent for further analysis of tumor material. Upon revision, 2 out of 3 MSI/IHC cases were found to be concordant with the MSH6 variant, and NGS showed that 4 discordant IHC results were sporadic rather than LS-associated tumors. In 1 case, somatic events explained the discordant phenotype. The use of reflex IHC mismatch repair testing, the current standard in most Western countries, may lead to the misdiagnosis of germline MSH6 variant carriers. The pathologist should point out that further diagnostics for inheritable colon cancer, including LS, should be considered in case of a strong positive family history. Germline DNA analysis of the mismatch repair genes, preferably as part of a larger gene panel, should therefore be considered in potential LS patients.
Collapse
Affiliation(s)
| | - Diantha Terlouw
- Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | - Carli M Tops
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Merel S van Kan
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Liselotte P van Hest
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Hans J P Gille
- Department of Clinical Genetics, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Floor A M Duijkers
- Department of Clinical Genetics, Amsterdam Medical Center, Amsterdam, The Netherlands
| | - Anja Wagner
- Department of Clinical Genetics, Erasmus MC Cancer Institute, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Ellis L Eikenboom
- Department of Clinical Genetics, Erasmus MC Cancer Institute, University Medical Center Rotterdam, Rotterdam, The Netherlands; Department of Gastroenterology and Hepatology, Erasmus MC Cancer Institute, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Tom G W Letteboer
- Department of Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Mirjam M de Jong
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Sanne W Bajwa-Ten Broeke
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Fonnet E Bleeker
- Department of Clinical Genetics, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Encarna B Gomez Garcia
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Niels de Wind
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - J Tom van Wezel
- Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | - Hans Morreau
- Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | - Manon Suerink
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Maartje Nielsen
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands.
| |
Collapse
|
2
|
Catena U, Della Corte L, Raffone A, Travaglino A, Lucci Cordisco E, Teodorico E, Masciullo V, Bifulco G, Di Spiezio Sardo A, Scambia G, Fanfani F. Fertility-sparing treatment for endometrial cancer and atypical endometrial hyperplasia in patients with Lynch Syndrome: Molecular diagnosis after immunohistochemistry of MMR proteins. Front Med (Lausanne) 2022; 9:948509. [PMID: 36091691 PMCID: PMC9452689 DOI: 10.3389/fmed.2022.948509] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 08/08/2022] [Indexed: 12/24/2022] Open
Abstract
Introduction Lynch Syndrome (LS) represents the hereditary condition that is most frequently associated with endometrial cancer (EC). The aim of this study is to assess the presence of Lynch Syndrome (LS) in young women with mismatch repair (MMR)-deficient atypical endometrial hyperplasia (AEH) and non-myoinvasive FIGO G1 endometrioid EC and its possible impact on the outcome of conservative treatment. Methods Six MMR-deficient cases identified from a previous cohort of 69 conservatively treated patients were selected to be screened for germline mutations in MMR genes. In each patient, the outcomes of conservative treatment for AEH and EEC, including response, relapse, progression, and pregnancy, were assessed. Results Five out of 6 patients underwent genetic test for LS. Three out of these 5 patients showed a positive genetic test. Patient 1 showed the c.942 + 2 T>A heterozygous variant of MSH2 mutation; after 12 months of complete response, she had relapse and progression of disease. Patient 4 showed the c.2459-1G>C variant of MSH2 mutation; after complete response, she failed to achieve pregnancy; she had relapse after 24 months and underwent hysterectomy. Patient 6 showed the c.803 + 1 heterozygous variant of PMS2 mutation; she had relapse of disease after 18 months from the first complete response and then underwent hysterectomy. Conclusions In this series, 3 out of 6 women with MMR-deficiency had LS. None of the patients achieved pregnancy, and those who responded to treatment had subsequent relapse of disease. Patients undergoing fertility-sparing treatment for atypical endometrial hyperplasia and endometrial cancer should perform MMR immunohistochemical analysis in order to screen LS.
Collapse
Affiliation(s)
- Ursula Catena
- Division of Gynecologic Surgery, Department of Woman, Child and Public Health, Fondazione Policlinico Universitario Agostino Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
- *Correspondence: Ursula Catena
| | - Luigi Della Corte
- Division of Gynecologic Surgery, Department of Woman, Child and Public Health, Fondazione Policlinico Universitario Agostino Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
- Department of Neuroscience, Reproductive Sciences and Dentistry, School of Medicine, University of Naples Federico II, Naples, Italy
| | - Antonio Raffone
- Department of Neuroscience, Reproductive Sciences and Dentistry, School of Medicine, University of Naples Federico II, Naples, Italy
| | - Antonio Travaglino
- Pathology Unit, Department of Advanced Biomedical Sciences, School of Medicine, University of Naples Federico II, Naples, Italy
| | - Emanuela Lucci Cordisco
- Medical Genetics Unit, epartment of Laboratory and Infectious Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Elena Teodorico
- Division of Gynecologic Surgery, Department of Woman, Child and Public Health, Fondazione Policlinico Universitario Agostino Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Valeria Masciullo
- Division of Gynecologic Surgery, Department of Woman, Child and Public Health, Fondazione Policlinico Universitario Agostino Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Giuseppe Bifulco
- Department of Public Health, University of Naples Federico II, Naples, Italy
| | | | - Giovanni Scambia
- Division of Gynecologic Surgery, Department of Woman, Child and Public Health, Fondazione Policlinico Universitario Agostino Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
- Catholic University of Sacred Heart, Rome, Italy
| | - Francesco Fanfani
- Division of Gynecologic Surgery, Department of Woman, Child and Public Health, Fondazione Policlinico Universitario Agostino Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
- Catholic University of Sacred Heart, Rome, Italy
| |
Collapse
|
3
|
Stinton C, Jordan M, Fraser H, Auguste P, Court R, Al-Khudairy L, Madan J, Grammatopoulos D, Taylor-Phillips S. Testing strategies for Lynch syndrome in people with endometrial cancer: systematic reviews and economic evaluation. Health Technol Assess 2021; 25:1-216. [PMID: 34169821 PMCID: PMC8273681 DOI: 10.3310/hta25420] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Lynch syndrome is an inherited genetic condition that is associated with an increased risk of certain cancers. The National Institute for Health and Care Excellence has recommended that people with colorectal cancer are tested for Lynch syndrome. Routine testing for Lynch syndrome among people with endometrial cancer is not currently conducted. OBJECTIVES To systematically review the evidence on the test accuracy of immunohistochemistry- and microsatellite instability-based strategies to detect Lynch syndrome among people who have endometrial cancer, and the clinical effectiveness and the cost-effectiveness of testing for Lynch syndrome among people who have been diagnosed with endometrial cancer. DATA SOURCES Searches were conducted in the following databases, from inception to August 2019 - MEDLINE ALL, EMBASE (both via Ovid), Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (both via Wiley Online Library), Database of Abstracts of Reviews of Effects, Health Technology Assessment Database (both via the Centre for Reviews and Dissemination), Science Citation Index, Conference Proceedings Citation Index - Science (both via Web of Science), PROSPERO international prospective register of systematic reviews (via the Centre for Reviews and Dissemination), NHS Economic Evaluation Database, Cost-Effectiveness Analysis Registry, EconPapers (Research Papers in Economics) and School of Health and Related Research Health Utilities Database. The references of included studies and relevant systematic reviews were also checked and experts on the team were consulted. REVIEW METHODS Eligible studies included people with endometrial cancer who were tested for Lynch syndrome using immunohistochemistry- and/or microsatellite instability-based testing [with or without mutL homologue 1 (MLH1) promoter hypermethylation testing], with Lynch syndrome diagnosis being established though germline testing of normal (non-tumour) tissue for constitutional mutations in mismatch repair. The risk of bias in studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool, the Consolidated Health Economic Reporting Standards and the Philips' checklist. Two reviewers independently conducted each stage of the review. A meta-analysis of test accuracy was not possible because of the number and heterogeneity of studies. A narrative summary of test accuracy results was provided, reporting test accuracy estimates and presenting forest plots. The economic model constituted a decision tree followed by Markov models for the impact of colorectal and endometrial surveillance, and aspirin prophylaxis with a lifetime time horizon. RESULTS The clinical effectiveness search identified 3308 studies; 38 studies of test accuracy were included. (No studies of clinical effectiveness of endometrial cancer surveillance met the inclusion criteria.) Four test accuracy studies compared microsatellite instability with immunohistochemistry. No clear difference in accuracy between immunohistochemistry and microsatellite instability was observed. There was some evidence that specificity of immunohistochemistry could be improved with the addition of methylation testing. There was high concordance between immunohistochemistry and microsatellite instability. The economic model indicated that all testing strategies, compared with no testing, were cost-effective at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year. Immunohistochemistry with MLH1 promoter hypermethylation testing was the most cost-effective strategy, with an incremental cost-effectiveness ratio of £9420 per quality-adjusted life-year. The second most cost-effective strategy was immunohistochemistry testing alone, but incremental analysis produced an incremental cost-effectiveness ratio exceeding £130,000. Results were robust across all scenario analyses. Incremental cost-effectiveness ratios ranged from £5690 to £20,740; only removing the benefits of colorectal cancer surveillance produced an incremental cost-effectiveness ratio in excess of the £20,000 willingness-to-pay threshold. A sensitivity analysis identified the main cost drivers of the incremental cost-effectiveness ratio as percentage of relatives accepting counselling and prevalence of Lynch syndrome in the population. A probabilistic sensitivity analysis showed, at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year, a 0.93 probability that immunohistochemistry with MLH1 promoter hypermethylation testing is cost-effective, compared with no testing. LIMITATIONS The systematic review excluded grey literature, studies written in non-English languages and studies for which the reference standard could not be established. Studies were included when Lynch syndrome was diagnosed by genetic confirmation of constitutional variants in the four mismatch repair genes (i.e. MLH1, mutS homologue 2, mutS homologue 6 and postmeiotic segregation increased 2). Variants of uncertain significance were reported as per the studies. There were limitations in the economic model around uncertainty in the model parameters and a lack of modelling of the potential harms of gynaecological surveillance and specific pathway modelling of genetic testing for somatic mismatch repair mutations. CONCLUSION The economic model suggests that testing women with endometrial cancer for Lynch syndrome is cost-effective, but that results should be treated with caution because of uncertain model inputs. FUTURE WORK Randomised controlled trials could provide evidence on the effect of earlier intervention on outcomes and the balance of benefits and harms of gynaecological cancer surveillance. Follow-up of negative cases through disease registers could be used to determine false negative cases. STUDY REGISTRATION This study is registered as PROSPERO CRD42019147185. FUNDING This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 25, No. 42. See the NIHR Journals Library website for further project information.
Collapse
Affiliation(s)
- Chris Stinton
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Mary Jordan
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Hannah Fraser
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Peter Auguste
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Rachel Court
- Warwick Medical School, University of Warwick, Coventry, UK
| | | | - Jason Madan
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Dimitris Grammatopoulos
- Institute of Precision Diagnostics and Translational Medicine, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | | |
Collapse
|
4
|
Manchana T, Ariyasriwatana C, Triratanachat S, Phowthongkum P. Lynch Syndrome in Thai Endometrial Cancer Patients. Asian Pac J Cancer Prev 2021; 22:1477-1483. [PMID: 34048176 PMCID: PMC8408393 DOI: 10.31557/apjcp.2021.22.5.1477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Lynch syndrome increases lifetime risk of endometrial cancer to 40-60%. Screening with molecular tumor testing for mismatch repair (MMR) proteins have been recommended. This study aims to evaluate the incidence of MMR deficiency and germline mutation in endometrial cancer Thai patients. METHODS Immunohistochemistry for MMR proteins, including MLH1, MSH2, MSH6 and PMS2 were tested in 166 surgical specimens. Patients who had MMR deficiencies were offered genetic counseling and a germline testing using gene-panel next generation sequencing. RESULTS Fifty-eight of 166 patients (34.9%) had one or more MMR deficiencies which were: MLH1 and PMS2 in 42 patients (25.3%), MSH2 and MSH6 in 11 patients (6.6%), and MSH6 in 5 patients (3.0%). Of the 40 patients (24.1%) who met the revised Bethesda guidelines, 19 patients (47.5%) had MMR deficiency. In contrast, MMR deficiency was found in 39 of the 126 patients (31.0%) who did not meet the revised Bethesda guidelines. A total of 27 patients with MMR deficiencies agreed to have germline genetic testing. Germline MMR mutations were detected in 5 patients (18.5%) including MSH6 (n=2), PMS2 (n=2), and MLH1 mutations (n=1). Incidental germline mutations in other genes were detected in 3 patients (1 BRCA1, 1 PTEN, and 1 BARD1). Among 5 Lynch syndrome patients, 2 patients (40%) did not meet the revised Bethesda guidelines. Eight patients who met the revised Bethesda Guidelines but having MMR proficiency had genetic testing, but no germline mutation was detected. CONCLUSION MMR deficiencies were detected in 34.9% of the endometrial cancer patients. Germline mutations were diagnosed in 3.0% of this cohort (5/166 patients). Lynch syndrome screening with MMR immunohistochemistry should be considered in all patients regardless of personal or family history of Lynch syndrome-related cancers.
Collapse
Affiliation(s)
- Tarinee Manchana
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Chai Ariyasriwatana
- Division of Gynecologic Pathology and Cytology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Surang Triratanachat
- Division of Gynecologic Pathology and Cytology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Prasit Phowthongkum
- Division of Medical Genetics, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| |
Collapse
|
5
|
Pauly N, Baert T, Schmutzler R, du Bois A, Schneider S, Rhiem K, Schömig-Markiefka B, Siemanowski J, Heikaus S, Traut A, Heitz F, Prader S, Ehmann S, Harter P, Ataseven B. Modern day screening for Lynch syndrome in endometrial cancer: the KEM experience. Arch Gynecol Obstet 2021; 304:975-984. [PMID: 33710393 DOI: 10.1007/s00404-021-06006-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 02/11/2021] [Indexed: 12/21/2022]
Abstract
PURPOSE Current guidelines for Lynch syndrome detection in endometrial cancer (EC) patients rely either on risk evaluation, based on personal/family history, or detection of mismatch repair (MMR) deficiency on tumor tissue. We present a combined screening algorithm for Lynch syndrome. METHODS In this study, 213 consecutive patients treated for EC at Kliniken Essen-Mitte between 2014 and 2018 were included. Personal/family history was evaluated by the Amsterdam II, revised Bethesda/German-DKG criteria and prediction model PREMM5. MMR testing was performed by immunohistochemistry (IHC) and/or polymerase chain reaction (PCR) based microsatellite analysis on tumor tissue. MLH1 promoter methylation analysis was performed in case of MLH1 loss or microsatellite instability. RESULTS Based on personal/family history 2/213 (Amsterdam II), 31/213 (revised Bethesda/German-DKG) and 149/213 (PREMM5) patients were identified as at risk for Lynch syndrome. MMR analysis was performed by IHC in 51.2%, by PCR in 32.4%, and in 16.4% of patients both methods were used. MMR deficiency was detected in 20.6% (44/213). Methylation analysis was performed in 27 patients of whom, 22 (81.4%) showed MLH1 promoter hypermethylation. Only 9% of MMR deficient patients were identified as at risk for Lynch syndrome by the revised Bethesda/German-DKG criteria. A pathogenic germline mutation was discovered in 3 out of 20 patients that underwent genetic testing. None of these patients were younger than 50 years or had a family history of Lynch syndrome-associated malignancies. CONCLUSION General MMR assessment is a feasible strategy to improve the detection of Lynch Syndrome in patients with EC.
Collapse
Affiliation(s)
- Nina Pauly
- Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte (KEM), Henricistrasse 92, 45136, Essen, Germany.
| | - Thaïs Baert
- Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte (KEM), Henricistrasse 92, 45136, Essen, Germany
- Department of Oncology, Laboratory of Tumour Immunology and Immunotherapy, ImmunOvar Research Group, KU Leuven, Leuven, Belgium
| | - Rita Schmutzler
- Center for Hereditary Breast and Ovarian Cancer, Center for Integrated Oncology (CIO), Medical Faculty, University Hospital Cologne, Cologne, Germany
| | - Andreas du Bois
- Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte (KEM), Henricistrasse 92, 45136, Essen, Germany
| | - Stephanie Schneider
- Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte (KEM), Henricistrasse 92, 45136, Essen, Germany
| | - Kerstin Rhiem
- Center for Hereditary Breast and Ovarian Cancer, Center for Integrated Oncology (CIO), Medical Faculty, University Hospital Cologne, Cologne, Germany
| | | | - Janna Siemanowski
- Institute of Pathology, University Hospital Cologne, Cologne, Germany
| | | | - Alexander Traut
- Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte (KEM), Henricistrasse 92, 45136, Essen, Germany
| | - Florian Heitz
- Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte (KEM), Henricistrasse 92, 45136, Essen, Germany
- Department for Gynecology With the Center for Oncologic Surgery, Charité Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Sonia Prader
- Department of Gynecology, Hospital Brixen, Brixen, Südtirol, Italy
| | - Sarah Ehmann
- Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte (KEM), Henricistrasse 92, 45136, Essen, Germany
| | - Philipp Harter
- Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte (KEM), Henricistrasse 92, 45136, Essen, Germany
| | - Beyhan Ataseven
- Department of Gynecology and Gynecologic Oncology, Kliniken Essen-Mitte (KEM), Henricistrasse 92, 45136, Essen, Germany
- Department of Obstetrics and Gynecology, University Hospital, LMU Munich, Munich, Germany
| |
Collapse
|
6
|
Gallon R, Gawthorpe P, Phelps RL, Hayes C, Borthwick GM, Santibanez-Koref M, Jackson MS, Burn J. How Should We Test for Lynch Syndrome? A Review of Current Guidelines and Future Strategies. Cancers (Basel) 2021; 13:406. [PMID: 33499123 PMCID: PMC7865939 DOI: 10.3390/cancers13030406] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 12/13/2022] Open
Abstract
International guidelines for the diagnosis of Lynch syndrome (LS) recommend molecular screening of colorectal cancers (CRCs) to identify patients for germline mismatch repair (MMR) gene testing. As our understanding of the LS phenotype and diagnostic technologies have advanced, there is a need to review these guidelines and new screening opportunities. We discuss the barriers to implementation of current guidelines, as well as guideline limitations, and highlight new technologies and knowledge that may address these. We also discuss alternative screening strategies to increase the rate of LS diagnoses. In particular, the focus of current guidance on CRCs means that approximately half of Lynch-spectrum tumours occurring in unknown male LS carriers, and only one-third in female LS carriers, will trigger testing for LS. There is increasing pressure to expand guidelines to include molecular screening of endometrial cancers, the most frequent cancer in female LS carriers. Furthermore, we collate the evidence to support MMR deficiency testing of other Lynch-spectrum tumours to screen for LS. However, a reliance on tumour tissue limits preoperative testing and, therefore, diagnosis prior to malignancy. The recent successes of functional assays to detect microsatellite instability or MMR deficiency in non-neoplastic tissues suggest that future diagnostic pipelines could become independent of tumour tissue.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - John Burn
- Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK; (P.G.); (R.L.P.); (C.H.); (G.M.B.); (M.S.-K.); (M.S.J.)
| |
Collapse
|
7
|
Testing for lynch syndrome in people with endometrial cancer using immunohistochemistry and microsatellite instability-based testing strategies - A systematic review of test accuracy. Gynecol Oncol 2020; 160:148-160. [PMID: 33190932 DOI: 10.1016/j.ygyno.2020.10.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 10/05/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Lynch syndrome is an inherited genetic condition that is associated with an increased risk of cancer, including endometrial and colorectal cancer. We assessed the test accuracy of immunohistochemistry and microsatellite instability-based testing (with or without MLH1 promoter methylation testing) for Lynch syndrome in women with endometrial cancer. METHODS We conducted a systematic review of literature published up to August 2019. We searched bibliographic databases, contacted experts and checked reference lists of relevant studies. Two reviewers conducted each stage of the review. RESULTS Thirteen studies were identified that included approximately 3500 participants. None of the studies was at low risk of bias in all domains. Data could not be pooled due to the small number of heterogeneous studies. Sensitivity ranged from 60.7-100% for immunohistochemistry, 41.7-100% for microsatellite instability-based testing, and 90.5-100% for studies combining immunohistochemistry, microsatellite instability-based testing, and MLH1 promoter methylation testing. Specificity ranged from 60.9-83.3% (excluding 1 study with highly selective inclusion criteria) for immunohistochemistry, 69.2-89.9% for microsatellite instability-based testing, and 72.4-92.3% (excluding 1 study with highly selective inclusion criteria) for testing strategies that included immunohistochemistry, microsatellite instability-based testing, and MLH1 promoter methylation. We found no statistically significant differences in test accuracy estimates (sensitivity, specificity) in head-to-head studies of immunohistochemistry versus microsatellite instability-based testing. Reported test failures were rare. CONCLUSIONS Sensitivity of the index tests were generally high, though most studies had much lower specificity. We found no evidence that test accuracy differed between IHC and MSI based strategies. The evidence base is currently small and at high risk of bias.
Collapse
|
8
|
Gordhandas S, Kahn RM, Gamble C, Talukdar N, Maddy B, Baltich Nelson B, Askin G, Christos PJ, Holcomb K, Caputo TA, Chapman-Davis E, Frey MK. Clinicopathologic features of endometrial cancer with mismatch repair deficiency. Ecancermedicalscience 2020; 14:1061. [PMID: 32582376 PMCID: PMC7302890 DOI: 10.3332/ecancer.2020.1061] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Indexed: 12/22/2022] Open
Abstract
The inclusion of DNA mismatch repair (MMR) evaluation as a standard of care for endometrial cancer management will result in a growing population of patients with MMR deficiency and negative germline Lynch syndrome testing (MMR-deficient). In this systematic review and study, the clinicopathologic features of endometrial cancer in patients with MMR-intact, MLH1 methylation positive, MMR-deficient or Lynch syndrome are evaluated. A systematic search of online databases between 1990 and 2018 identified studies of endometrial cancer patients with tumour testing (MMR protein immunohistochemistry or microsatellite instability) and germline assessment for Lynch syndrome. Extracted data included tumour testing, germline genetic testing, age, body mass index (BMI), family history, tumour stage, grade and histologic type. Associations between MMR-intact, MLH1 methylation positive, MMR-deficient and Lynch syndrome groups were analysed using descriptive statistics. The comprehensive search produced 4,400 publications, 29 met inclusion criteria. A total of 7,057 endometrial cancer cases were identified, 1,612 with abnormal immunohistochemistry, 977 with microsatellite instability. Nine-hundred patients underwent germline genetic testing, identifying 212 patients with Lynch syndrome. Patients in the Lynch syndrome and MMR-deficient groups were significantly younger than patients in the MMR-intact and MLH1 methylation positive groups. Patients with MMR-intact tumours had the highest BMI, followed by MMR-deficient, then Lynch syndrome. MMR-intact tumours were more likely to be grade I at diagnosis than other groups. Patients with Lynch syndrome and MMR-deficient tumours were less likely to have stage I disease as compared to patients with MMR-intact tumours. Endometrial cancer patients with MMR-deficient tumours have similar features to those with germline Lynch syndrome mutations, including age, grade, histology and stage. Even in the absence of a germline mutation, tumour evaluation for MMR status may have important clinical implications.
Collapse
Affiliation(s)
- Sushmita Gordhandas
- Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, USA
| | - Ryan M Kahn
- Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, USA
| | - Charlotte Gamble
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, USA
| | - Nizam Talukdar
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, USA
| | - Brandon Maddy
- Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, USA
| | - Becky Baltich Nelson
- Department of Information Technologies and Services, Weill Cornell Medical College, New York, NY, USA
| | - Gulce Askin
- Division of Biostatistics and Epidemiology, Department of Healthcare Policy & Research, Weill Cornell Medicine, New York, NY, USA
| | - Paul J Christos
- Division of Biostatistics and Epidemiology, Department of Healthcare Policy & Research, Weill Cornell Medicine, New York, NY, USA
| | - Kevin Holcomb
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, USA
| | - Thomas A Caputo
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, USA
| | - Eloise Chapman-Davis
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, USA
| | - Melissa K Frey
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, NY, USA
| |
Collapse
|
9
|
Cost-effectiveness analysis of reflex testing for Lynch syndrome in women with endometrial cancer in the UK setting. PLoS One 2019; 14:e0221419. [PMID: 31469860 PMCID: PMC6716649 DOI: 10.1371/journal.pone.0221419] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 08/06/2019] [Indexed: 12/20/2022] Open
Abstract
Background Lynch syndrome is a hereditary cancer syndrome caused by constitutional pathogenic variants in the DNA mismatch repair (MMR) system, leading to increased risk of colorectal, endometrial and other cancers. The study aimed to identify the incremental costs and consequences of strategies to identify Lynch syndrome in women with endometrial cancer. Methods A decision-analytic model was developed to evaluate the relative cost-effectiveness of reflex testing strategies for identifying Lynch syndrome in women with endometrial cancer taking the NHS perspective and a lifetime horizon. Model input parameters were sourced from various published sources. Consequences were measured using quality-adjusted life years (QALYs). A cost-effectiveness threshold of £20 000/QALY was used. Results Reflex testing for Lynch syndrome using MMR immunohistochemistry and MLH1 methylation testing was cost-effective versus no testing, costing £14 200 per QALY gained. There was uncertainty due to parameter imprecision, with an estimated 42% chance this strategy is not cost-effective compared with no testing. Age had a significant impact on cost-effectiveness, with testing not predicted to be cost-effective in patients aged 65 years and over. Conclusions Testing for Lynch syndrome in younger women with endometrial cancer using MMR immunohistochemistry and MLH1 methylation testing may be cost-effective. Age cut-offs may be controversial and adversely affect implementation.
Collapse
|
10
|
Kahn RM, Gordhandas S, Maddy BP, Baltich Nelson B, Askin G, Christos PJ, Caputo TA, Chapman-Davis E, Holcomb K, Frey MK. Universal endometrial cancer tumor typing: How much has immunohistochemistry, microsatellite instability, and MLH1 methylation improved the diagnosis of Lynch syndrome across the population? Cancer 2019; 125:3172-3183. [PMID: 31150123 DOI: 10.1002/cncr.32203] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 04/23/2019] [Accepted: 04/24/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND Universal tumor testing for defective DNA mismatch repair (MMR) is recommended for all women diagnosed with endometrial cancer to identify those with underlying Lynch syndrome. However, the effectiveness of these screening methods in identifying individuals with Lynch syndrome across the population has not been well studied. The aim of this study was to evaluate outcomes of MMR immunohistochemistry (IHC), mutL homolog 1 (MLH1) methylation, and microsatellite instability (MSI) analysis among patients with endometrial cancer. METHODS A complete systematic search of online databases (PubMed, EMBASE, MEDLINE, and the Cochrane Library) for 1990-2018 was performed. A DerSimonian-Laird random effects model meta-analysis was used to estimate the weighted prevalence of Lynch syndrome diagnoses. RESULTS The comprehensive search produced 4400 publications. Twenty-nine peer-reviewed studies met the inclusion criteria. Patients with endometrial cancer (n = 6649) were identified, and 206 (3%) were confirmed to have Lynch syndrome through germline genetic testing after positive universal tumor molecular screening. Among 5917 patients who underwent tumor IHC, 28% had abnormal staining. Among 3140 patients who underwent MSI analysis, 31% had MSI. Among patients with endometrial cancer, the weighted prevalence of Lynch syndrome germline mutations was 15% (95% confidence interval [CI], 11%-18%) with deficient IHC staining and 19% (95% CI, 13%-26%) with a positive MSI analysis. Among 1159 patients who exhibited a loss of MLH1 staining, 143 (13.7%) were found to be MLH1 methylation-negative among those who underwent methylation testing, and 32 demonstrated a germline MLH1 mutation (2.8% of all absent MLH1 staining cases and 22.4% of all MLH1 methylation-negative cases). Forty-three percent of patients with endometrial cancer who were diagnosed with Lynch syndrome via tumor typing would have been missed by family history-based screening alone. CONCLUSIONS Despite the widespread implementation of universal tumor testing in endometrial cancer, data regarding testing results remain limited. This study provides predictive values that will help practitioners to evaluate abnormal results in the context of Lynch syndrome and aid them in patient counseling.
Collapse
Affiliation(s)
- Ryan M Kahn
- Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, New York
| | - Sushmita Gordhandas
- Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, New York
| | - Brandon Paul Maddy
- Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, New York
| | - Becky Baltich Nelson
- Department of Information Technologies and Services, Weill Cornell Medical College, New York, New York
| | - Gulce Askin
- Clinical and Translational Science Center, Department of Biostatistics and Epidemiology, Weill Cornell Medical College, New York, New York
| | - Paul J Christos
- Clinical and Translational Science Center, Department of Biostatistics and Epidemiology, Weill Cornell Medical College, New York, New York
| | - Thomas A Caputo
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, New York
| | - Eloise Chapman-Davis
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, New York
| | - Kevin Holcomb
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, New York
| | - Melissa K Frey
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, New York
| |
Collapse
|
11
|
Ryan NAJ, Glaire MA, Blake D, Cabrera-Dandy M, Evans DG, Crosbie EJ. The proportion of endometrial cancers associated with Lynch syndrome: a systematic review of the literature and meta-analysis. Genet Med 2019; 21:2167-2180. [PMID: 31086306 PMCID: PMC8076013 DOI: 10.1038/s41436-019-0536-8] [Citation(s) in RCA: 135] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 04/25/2019] [Indexed: 12/21/2022] Open
Abstract
Purpose Endometrial cancer (EC) is often the sentinel cancer in women with Lynch syndrome (LS). However, efforts to implement universal LS screening in EC patients have been hampered by a lack of evidence detailing the proportion of EC patients that would be expected to screen positive for LS. Methods Studies were identified by electronic searches of Medline, Embase, Cochrane CENTRAL and Web of Science. Proportions of test positivity were calculated by random and fixed-effects meta-analysis models. I2 score was used to assess heterogeneity across studies. Results Fifty-three studies, including 12,633 EC patients, met the inclusion criteria. The overall proportion of endometrial tumors with microsatellite instability or mismatch repair (MMR) deficiency by immunohistochemistry (IHC) was 0.27 (95% confidence interval [CI] 0.25–0.28, I2: 71%) and 0.26 (95% CI 0.25–0.27, I2: 88%), respectively. Of those women with abnormal tumor testing, 0.29 (95% CI 0.25–0.33, I2: 83%) had LS-associated pathogenic variants on germline testing; therefore around 3% of ECs can be attributed to LS. Preselection of EC cases did increase the proportion of germline LS diagnoses. Conclusion The current study suggests that prevalence of LS in EC patients is approximately 3%, similar to that of colorectal cancer patients; therefore our data support the implementation of universal EC screening for LS.
Collapse
Affiliation(s)
- N A J Ryan
- Division of Cancer Sciences, Faculty of Biology, Medicine and Health, University of Manchester, St Mary's Hospital, Manchester, UK.,Division of Evolution and Genomic Medicine, University of Manchester, St Mary's Hospital, Manchester, UK
| | - M A Glaire
- Tumor Genomics and Immunology Group, The Oxford Centre for Cancer Gene Research, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - D Blake
- Department of Obstetrics and Gynaecology, St James's University Hospital, The Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - M Cabrera-Dandy
- Lancashire Hospitals NHS Trust, Royal Blackburn Hospital, Blackburn, UK
| | - D G Evans
- Division of Evolution and Genomic Medicine, University of Manchester, St Mary's Hospital, Manchester, UK.,Manchester Centre for Genomic Medicine, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - E J Crosbie
- Division of Cancer Sciences, Faculty of Biology, Medicine and Health, University of Manchester, St Mary's Hospital, Manchester, UK. .,Department of Obstetrics and Gynaecology, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK.
| |
Collapse
|
12
|
Wang A, McCracken J, Li Y, Xu L. The practice of universal screening for Lynch syndrome in newly diagnosed endometrial carcinoma. Health Sci Rep 2018; 1:e43. [PMID: 30623082 PMCID: PMC6266449 DOI: 10.1002/hsr2.43] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 01/14/2018] [Accepted: 03/28/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Lynch syndrome (LS) accounts for 5% of all endometrial cancer (EC) cases and 4% of all lifetime risk of developing colorectal cancer. While current guidelines recommend LS screening for all patients with newly diagnosed colorectal cancer, there is no such guideline for screening patients with EC. DISCUSSION This review addresses LS screening and discusses algorithms for testing patients in the setting of newly diagnosed EC. CONCLUSION The successful diagnosis of LS has important implications, including prevention of LS-associated cancers among relatives and immunotherapy recommendations for patients with advanced EC and loss of expression of mismatch repair immunohistochemistry and microsatellite instability positive following failure of traditional treatment.
Collapse
Affiliation(s)
- Aifen Wang
- Department of Obstetrics and Gynecology, Zhangjiagang HospitalNanjing University of Chinese MedicineJiangsuChina215600
| | - Jenna McCracken
- Department of PathologyDuke University School of MedicineDurhamNCUSA
| | - Yanjing Li
- Department of PathologyDuke University School of MedicineDurhamNCUSA
| | - Lingfan Xu
- Department of PathologyDuke University School of MedicineDurhamNCUSA
| |
Collapse
|
13
|
Feng YC, Ji WL, Yue N, Huang YC, Ma XM. The relationship between the PD-1/PD-L1 pathway and DNA mismatch repair in cervical cancer and its clinical significance. Cancer Manag Res 2018; 10:105-113. [PMID: 29403308 PMCID: PMC5783151 DOI: 10.2147/cmar.s152232] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background According to recent clinical observations, deficient DNA mismatch repair (dMMR) is capable of improving antitumor effects of the PD-1/PD-L1 pathway, suggesting that dMMR may act as a prognostic indicator of PD-1/PD-L1 antibody drugs. In this study, we examined the dMMR and PD-1/PD-L1 expression, as well as explored the correlation of dMMR status with PD-1/PD-L1 expression in cervical cancer patients, in order to optimize cervical cancer patient selection for PD-1/PD-L1 antibody drug treatment, which is helpful to avoid adverse effects and keep costs manageable. Methods Sixty-six tissue samples from patients with squamous cell carcinoma were collected, and data of their clinical characteristics were also gathered. Based on these samples, the expression levels of MLH1, MSH2, and PD-L1 in cancer cells were tested by immunohistochemical assay (IHC). Moreover, PD-1/PD-L1 expression in tumor-invading lymphocytes (TILs) was detected by IHC as well. Six single-nucleotide-repeat markers of microsatellite instability (MSI), including NR-27, MONO-27, BAT-25, NR-24, NR-21, and BAT-26, were tested by capillary electrophoresis sequencer analysis. According to expression of MLH1, MSH2 and the MSI test, all 66 cases were divided into dMMR or proficient DNA mismatch repair (pMMR) groups. The comparisons of dMMR and PD-L1 in cancer cells and of PD-1/PD-L1 in TILs were conducted categorized by age, childbearing history, history of abortion, ethnicity, and cancer cell differentiation subgroup. Furthermore, PD-L1 levels in cancer cells and PD-1/PD-L1 in TILs were analyzed and compared in both dMMR and pMMR subgroups. Results Of the patient samples, 25.8% were associated with dMMR. PD-L1 in cancer cells, PD-L1 in TILs, and PD-1 in TILs took up 59.1%, 47.0%, and 60.6%, respectively. The data indicated that both dMMR and PD-L1 overexpression resulted from lower cancer differentiation, more incidences of childbearing, and a history of abortion. Abortion could significantly increase PD-1 expression levels in TILs. Additionally, more incidence of childbearing or older age (35–55 years) was able to upregulate PD-L1 expression in TILs. Statistical difference of PD-L1 in cancer cells could be observed between dMMR and pMMR subgroups. In the dMMR group, PD-L1 in cancer cells and PD-1 in TILs had no correlation (rs=0.161, p=0.537), but in the pMMR group, they had good correlation (rs=0.645, p<0.001). Conclusion According to prior studies and our own experiments, PD-L1 in both cancer cells and TILs and PD-1 in TILs are widely observed in cervical cancer patients, indicating that there may be potential to apply PD-1/PD-L1 antibody drugs in cervical cancer. dMMR patients are associated with higher PD-L1 expression compared with pMMR ones, which suggested that PD-1/PD-L1 antibody drugs may work well in dMMR cervical cancer patients. Moreover, in patients with more incidences of childbearing or abortion, dMMR may be a molecular detection target for clinical application of PD-1/PD-L1 antibody drugs.
Collapse
Affiliation(s)
- Yang-Chun Feng
- Clinical Laboratory Center, The First Affiliated Hospital of Xinjiang Medical University.,Clinical Laboratory Center
| | - Wen-Li Ji
- Clinical Pathology Center, Tumor Hospital Affiliated to Xinjiang Medical University, Urumqi, People's Republic of China
| | - Na Yue
- Clinical Pathology Center, Tumor Hospital Affiliated to Xinjiang Medical University, Urumqi, People's Republic of China
| | | | - Xiu-Min Ma
- Clinical Laboratory Center, The First Affiliated Hospital of Xinjiang Medical University
| |
Collapse
|
14
|
Libera L, Sahnane N, Carnevali IW, Cimetti L, Cerutti R, Chiaravalli AM, Riva C, Tibiletti MG, Sessa F, Furlan D. Microsatellite analysis of sporadic and hereditary gynaecological cancer in routine diagnostics. J Clin Pathol 2017; 70:792-797. [DOI: 10.1136/jclinpath-2017-204348] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 03/14/2017] [Accepted: 03/15/2017] [Indexed: 11/04/2022]
Abstract
Microsatellite instability (MSI) testing is tricky in gynaecological cancers (GC). Thus, we aimed to describe the instability patterns to improve MSI test interpretation in sporadic and hereditary GCs. Ninety-five cases, including uterine and ovarian cancers, with known genetic and immunohistochemical (IHC) features, were analysed for MSI by a mononucleotide repeats pentaplex (MRP). We identified 13 ambiguous cases that did not fully meet MSI criteria (‘borderline’ cases, B-MSI), which were mainly represented by MSH2/MSH6-deficient and Lynch syndrome cases. Also, we evaluated nine additional loci of candidate MSI markers that did not improve the detection of MSI cases, but might be useful for discordant or borderline samples. In conclusion, although MSI and IHC test are highly concordant, a subset of ambiguous MSI cases deserves a careful interpretation in particular when MSH2/MSH6 are involved.RPL22andSRPRtesting may be useful to integrate MRP panel for the analysis of critical cases.
Collapse
|