Nisha Modi, Amit Varma, Rajesh Patidar, Vrushali Gadre, Srushti Karmarkar
{"title":"Differential Expression of TLE1 in Small Round Cell Tumors: A Proposed Solution for Challenging Differentials Impacting Treatment Strategies.","authors":"Nisha Modi, Amit Varma, Rajesh Patidar, Vrushali Gadre, Srushti Karmarkar","doi":"10.1177/10668969251339810","DOIUrl":null,"url":null,"abstract":"<p><p><i>Introduction.</i> Small round cell tumors (SRCTs) represent a heterogeneous group of neoplasms with overlapping histological features but varying origins, prognoses, and treatments. TLE1 is a well-established marker for synovial sarcoma (SS). However, TLE1's diagnostic utility is limited by its expression in a broad range of tumor types, reducing its specificity for SS. This study explores TLE1 expression across SRCTs and proposes an immunohistochemical algorithm to enhance diagnostic accuracy. <i>Methods.</i> This retrospective, single-center observational study, conducted from 2019 to 2024, reviewed pathology records for SRCTs. TLE1 staining was evaluated using the immunoreactive score system, categorized as follows: 0 (negative), 1+ (weak), 2+ (moderate), and 3+ (strong). <i>Results.</i> A total of 301 SRCTs were evaluated with diverse distribution: neuroendocrine neoplasms (21%, n = 63), extraskeletal Ewing sarcoma (15%, n = 45), lymphoblastic lymphoma (11%, n = 34), and poorly differentiated synovial sarcoma (PDSS) (8%, n = 24). TLE1 expression of 3 + was most frequently observed in PDSS (75%, 18/24). Other tumors with TLE1 3 + included extraskeletal Ewing sarcoma, extracutaneous malignant melanoma, neuroendocrine neoplasms, rhabdomyosarcoma, and endometrial stromal sarcoma. TLE1 2 + was noted in lymphoblastic lymphoma and desmoplastic SRCT, while TLE1 1 + was seen in some gastrointestinal stromal tumors. The remaining specimens were negative for TLE1. These findings led to a diagnostic framework for SRCTs based on TLE1 expression patterns. <i>Conclusions.</i> Although TLE1 is a key marker for SS, its expression in other tumors can present diagnostic challenges. Integrating clinical features, histological assessment, and a panel of immunohistochemistry markers is essential for accurate diagnosis and effective management of SRCTs.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969251339810"},"PeriodicalIF":0.9000,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Surgical Pathology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1177/10668969251339810","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"PATHOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Introduction. Small round cell tumors (SRCTs) represent a heterogeneous group of neoplasms with overlapping histological features but varying origins, prognoses, and treatments. TLE1 is a well-established marker for synovial sarcoma (SS). However, TLE1's diagnostic utility is limited by its expression in a broad range of tumor types, reducing its specificity for SS. This study explores TLE1 expression across SRCTs and proposes an immunohistochemical algorithm to enhance diagnostic accuracy. Methods. This retrospective, single-center observational study, conducted from 2019 to 2024, reviewed pathology records for SRCTs. TLE1 staining was evaluated using the immunoreactive score system, categorized as follows: 0 (negative), 1+ (weak), 2+ (moderate), and 3+ (strong). Results. A total of 301 SRCTs were evaluated with diverse distribution: neuroendocrine neoplasms (21%, n = 63), extraskeletal Ewing sarcoma (15%, n = 45), lymphoblastic lymphoma (11%, n = 34), and poorly differentiated synovial sarcoma (PDSS) (8%, n = 24). TLE1 expression of 3 + was most frequently observed in PDSS (75%, 18/24). Other tumors with TLE1 3 + included extraskeletal Ewing sarcoma, extracutaneous malignant melanoma, neuroendocrine neoplasms, rhabdomyosarcoma, and endometrial stromal sarcoma. TLE1 2 + was noted in lymphoblastic lymphoma and desmoplastic SRCT, while TLE1 1 + was seen in some gastrointestinal stromal tumors. The remaining specimens were negative for TLE1. These findings led to a diagnostic framework for SRCTs based on TLE1 expression patterns. Conclusions. Although TLE1 is a key marker for SS, its expression in other tumors can present diagnostic challenges. Integrating clinical features, histological assessment, and a panel of immunohistochemistry markers is essential for accurate diagnosis and effective management of SRCTs.
期刊介绍:
International Journal of Surgical Pathology (IJSP) is a peer-reviewed journal published eight times a year, which offers original research and observations covering all major organ systems, timely reviews of new techniques and procedures, discussions of controversies in surgical pathology, case reports, and images in pathology. This journal is a member of the Committee on Publication Ethics (COPE).