{"paper_id":"6dcec534-0a53-4621-afd8-a949b4160f0c","body_text":"Abstract\nBackground\nThe prognostic significance of adenomyosis in endometrial cancer (EC) remains controversial. Although several studies have suggested an association between adenomyosis and favorable tumor characteristics or improved survival outcomes, it remains unclear whether this relationship persists after adjustment for established clinicopathologic prognostic factors.\nAim\nTo investigate the impact of coexisting adenomyosis on clinicopathologic characteristics and survival outcomes in patients with endometrioid-type endometrial cancer.\nMethods\nThis retrospective cohort study included 527 consecutive patients with histologically confirmed endometrioid-type endometrial cancer who underwent primary surgical treatment between January 2010 and May 2025 at a tertiary gynecologic oncology center. Patients were categorized according to the presence or absence of adenomyosis identified in hysterectomy specimens. Clinicopathologic characteristics were compared between groups. Disease-free survival (DFS) and overall survival (OS) were evaluated using the Kaplan–Meier method and Cox proportional hazards regression analyses.\nResults\nAdenomyosis was identified in 154 patients (29.2%). No significant differences were observed between patients with and without adenomyosis regarding age, tumor grade, FIGO stage, myometrial invasion, lymphovascular space invasion (LVSI), lymph node metastasis, or adjuvant treatment (all p > 0.05). Kaplan–Meier analysis demonstrated no significant differences in either DFS or OS according to adenomyosis status (log-rank p = 0.626 and p = 0.697, respectively). In multivariable analysis, LVSI remained the only independent predictor of poorer DFS (HR 2.15, 95% CI 1.02–4.53, p = 0.044), whereas older age (HR 1.08, 95% CI 1.06–1.12, p < 0.001), grade 3 histology (HR 2.11, 95% CI 1.26–3.54, p = 0.005), advanced FIGO stage (HR 1.92, 95% CI 1.18–2.93, p = 0.003), and positive peritoneal cytology (HR 4.47, 95% CI 1.20–16.64, p = 0.026) were independently associated with poorer OS. Adenomyosis was not identified as an independent prognostic factor for either DFS or OS.\nConclusion\nIn this cohort of patients with endometrioid-type endometrial cancer, coexisting adenomyosis was not independently associated with distinct clinicopathologic features, disease-free survival, or overall survival. Established clinicopathologic factors remained the primary determinants of oncologic outcomes.\nSimilar content being viewed by others\nData availability\nIn view of the confidentiality and privacy of the participants, the datasets and supporting materials are available from the corresponding author upon reasonable request.\nReferences\nRaimondo D, Raffone A, Travaglino A et al (2022) Impact of adenomyosis on the prognosis of patients with endometrial cancer. Int J Gynaecol Obstet 157(2):265–270. https://doi.org/10.1002/ijgo.13818\nMatsuo K, Cahoon SS, Gualtieri M et al (2014) Significance of adenomyosis on tumor progression and survival outcome of endometrial cancer. Ann Surg Oncol 21(13):4246–4255. https://doi.org/10.1245/s10434-014-3880-6\nLa Torre F, Hurni Y, Farsi E et al (2025) Adenomyosis associated with endometrial cancer: Possible correlation with pathological, immunohistochemical and molecular characteristics. 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BMC Cancer 25(1):1574. https://doi.org/10.1186/s12885-025-14815-4\nCelik E, Goksever Celik H, Sozen H et al (2022) The effect of adenomyosis on endometrial cancer: a university hospital-based cohort study. J Obstet Gynaecol 42(1):158–165. https://doi.org/10.1080/01443615.2021.1980508\nHertlein L, Rath J, Zeder-Goss C et al (2017) Coexistence of adenomyosis uteri and endometrial cancer is associated with an improved prognosis compared with endometrial cancer only. Oncol Lett 14(3):3302–3308. https://doi.org/10.3892/ol.2017.6592\nSimsek E, Yildiz S, Karakas S et al (2023) Effect of adenomyosis on prognosis of patients with endometrial cancer. Rev Assoc Med Bras (1992) 69(7):e20221720. https://doi.org/10.1590/1806-9282.20221720\nYilmaz A, Cokmez H, Gulbahar A (2022) Effect of coexisting adenomyosis on patients with endometrioid adenocarcinoma: determination of intraoperative risk factors for tumor metastasis and estimation of prognosis. J Cancer Res Ther 18(3):599–602. https://doi.org/10.4103/jcrt.JCRT_1277_20\nWang DG, Ji LM, Jia CL et al (2023) Effect of coexisting adenomyosis on tumour characteristics and prognosis of endometrial cancer: A systematic review and meta-analysis. Taiwan J Obstet Gynecol 62(5):640–650. https://doi.org/10.1016/j.tjog.2023.07.004\nBuyuksahin LG, Ibanoglu MC, Ozturk AC et al (2024) Does coexistence of endometrial cancer and adenomyosis affect survival outcomes? A retrospective cohort study. Eur J Gynaecol Oncol 45(2):118–126. https://doi.org/10.22514/ejgo.2023.112\nFunding\nNone.\nAuthor information\nAuthors and Affiliations\nContributions\nYakup Yalcin: Conceptualization; methodology, data collection, writing original draft, review & editing. Kemal Ozerkan: Conceptualization; methodology, data collection. All authors meet the criteria for authorship, have approved the final article and that all those entitled to authorship are listed as authors.\nCorresponding author\nEthics declarations\nEthical compliance\nAll procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the Helsinki Declaration and its later amendments or comparable ethical standards. This study was approved by the Bursa Uludağ University Clinical Research Ethics Committee (Protocol No. 2026/157/6 − 5). Due to the retrospective nature of the study, the ethics committee exempted the requirement for informed consent.\nConflict of interest\nThe authors declare no potential conflicts of interest with respect to the research, authorship, or publication of this article.\nAdditional information\nPublisher’s note\nSpringer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.\nRights and permissions\nSpringer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.\nAbout this article\nCite this article\nYalcin, Y., Ozerkan, K. Adenomyosis is not an independent prognostic factor in endometrioid-type endometrial cancer. Ir J Med Sci (2026). https://doi.org/10.1007/s11845-026-04535-4\nReceived:\nAccepted:\nPublished:\nVersion of record:\nDOI: https://doi.org/10.1007/s11845-026-04535-4","source_license":"public-domain-us","license_restricted":false}