{"title":"Prevalence and type of MMR expression heterogeneity in colorectal adenocarcinoma: therapeutic implications and reporting.","authors":"Federica Grillo, Valentina Angerilli, Paola Parente, Alessandro Vanoli, Claudio Luchini, Stefania Sciallero, Alberto Puccini, Francesca Bergamo, Sara Lonardi, Nicola Valeri, Luca Mastracci, Matteo Fassan","doi":"10.1007/s00428-023-03726-z","DOIUrl":null,"url":null,"abstract":"<p><p>Mismatch repair (MMR) immunohistochemical (IHC) evaluation has entered pathology routine practice as the first-line screening method to identify patients with MMR deficient (MMRd)/microsatellite instability (MSI) colorectal cancer (CRC), and its misdiagnosis may significantly impact the personalization of CRC patient care. To determine the prevalence of MMR protein intratumor heterogeneity in real-world practice, we collected a series of 8282 CRCs tested for MMR proteins in the setting of Lynch syndrome universal screening. Four heterogenous cases were also investigated for tumor infiltrating lymphocytes count, MSI status, and consensus molecular subtypes by Nanostring nCounter® Platform. Overall, 1056 (12.8%) CRCs showed a MMR altered status, with 46 cases showing a heterogeneous MMR profile (0.56% of the total, and 4.36% of all MMRd cases). To conclude, the authors make some critical remarks regarding the approach to MMR heterogeneity in clinical practice and routine diagnostics.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":null,"pages":null},"PeriodicalIF":3.4000,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Virchows Archiv","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1007/s00428-023-03726-z","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2023/12/23 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"PATHOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Mismatch repair (MMR) immunohistochemical (IHC) evaluation has entered pathology routine practice as the first-line screening method to identify patients with MMR deficient (MMRd)/microsatellite instability (MSI) colorectal cancer (CRC), and its misdiagnosis may significantly impact the personalization of CRC patient care. To determine the prevalence of MMR protein intratumor heterogeneity in real-world practice, we collected a series of 8282 CRCs tested for MMR proteins in the setting of Lynch syndrome universal screening. Four heterogenous cases were also investigated for tumor infiltrating lymphocytes count, MSI status, and consensus molecular subtypes by Nanostring nCounter® Platform. Overall, 1056 (12.8%) CRCs showed a MMR altered status, with 46 cases showing a heterogeneous MMR profile (0.56% of the total, and 4.36% of all MMRd cases). To conclude, the authors make some critical remarks regarding the approach to MMR heterogeneity in clinical practice and routine diagnostics.
期刊介绍:
Manuscripts of original studies reinforcing the evidence base of modern diagnostic pathology, using immunocytochemical, molecular and ultrastructural techniques, will be welcomed. In addition, papers on critical evaluation of diagnostic criteria but also broadsheets and guidelines with a solid evidence base will be considered. Consideration will also be given to reports of work in other fields relevant to the understanding of human pathology as well as manuscripts on the application of new methods and techniques in pathology. Submission of purely experimental articles is discouraged but manuscripts on experimental work applicable to diagnostic pathology are welcomed. Biomarker studies are welcomed but need to abide by strict rules (e.g. REMARK) of adequate sample size and relevant marker choice. Single marker studies on limited patient series without validated application will as a rule not be considered. Case reports will only be considered when they provide substantial new information with an impact on understanding disease or diagnostic practice.