{"paper_id":"eaedf2b5-2919-446c-a275-b69ebcbc69ab","body_text":"Abstract\nBackground\nPolypoid endometriosis (PEM) is a rare form of endometriosis characterized by polyp-like lesions and atypical clinical and imaging features. Although PEM is generally benign, extensive abdominopelvic involvement and unusual manifestations may create substantial diagnostic challenges. Massive hemorrhagic ascites is exceptionally uncommon in PEM, and its clinical characteristics and management remain poorly described.\nCase presentation\nA 41-year-old woman presented with progressive postmenstrual abdominal distension for four months, with marked worsening during the last week. She had a history of adenomyosis and surgically confirmed ovarian endometriosis. Imaging demonstrated mixed adnexal masses, massive ascites, and omental thickening, while serum CA125 and CA19-9 levels were elevated. Approximately 4000 mL of hemorrhagic ascites was drained by ultrasound-guided paracentesis, and cytologic examination showed no malignant cells. Laparoscopic exploration revealed extensive dense adhesions and multiple friable polyp-like lesions diffusely involving the abdominopelvic cavity, omentum, and mesentery. Intraoperative frozen-section examination revealed benign findings, and final histopathological examination confirmed PEM. Whole-exome sequencing identified a BMP4 p.H251Y missense variant. Postoperatively, the patient received 6 courses of GnRHa therapy followed by Dienogest, with no evidence of recurrence during 9 months of follow-up.\nConclusions\nThis case highlights an exceptionally rare presentation of PEM characterized with massive hemorrhagic ascites and extensive abdominopelvic lesions, closely mimicking advanced gynecologic malignancy. Increased awareness of this unusual presentation, together with appropriate clinical assessment, may facilitate accurate diagnosis and help avoid unnecessarily radical surgery. Given the limited number of reported PEM cases, further studies are needed to clarify the pathogenesis and optimal postoperative management of this rare disease.\nSimilar content being viewed by others\nAbbreviations\n- ADC:\n-\nApparent Diffusion Coefficient\n- AFP:\n-\nAlpha-Fetoprotein\n- AM:\n-\nAdenomyosis\n- BMP4:\n-\nBone Morphogenetic Protein 4\n- CA125:\n-\nCarbohydrate Antigen 125\n- CA15-3:\n-\nCarbohydrate Antigen 15-3\n- CA19-9:\n-\nCarbohydrate Antigen 19-9\n- CA72-4:\n-\nCarbohydrate Antigen 72-4\n- CEA:\n-\nCarcinoembryonic Antigen\n- COCs:\n-\nCombined Oral Contraceptives\n- CT:\n-\nComputed Tomography\n- EM:\n-\nEndometriosis\n- ER:\n-\nEstrogen Receptor\n- GnRHa:\n-\nGonadotropin-releasing Hormone Analogs\n- HE4:\n-\nHuman Epididymis Protein 4\n- MRI:\n-\nMagnetic Resonance Imaging\n- NM:\n-\nNot Mentioned\n- PEM:\n-\nPolypoid Endometriosis\n- PR:\n-\nProgesterone Receptor\n- SNV:\n-\nSingle Nucleotide Varian\n- WES:\n-\nWhole-exome Sequencing\nAcknowledgements\nNot applicable.\nFunding\nThis study was supported by the National Natural Science Foundation of China (No.82373334).\nAuthor information\nAuthors and Affiliations\nCorresponding author\nEthics declarations\nEthics approval and consent to participate\nThis study was approved by the Ethics Committee of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology (No.TJ-IRB202604023), according to the 1975 Declaration of Helsinki and its later ethical standards.\nConsent for publication\nWritten informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the editor of this journal.\nCompeting interests\nThe authors declare no competing interests.\nAdditional information\nPublisher’s note\nSpringer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.\nSupplementary Information\nRights and permissions\nOpen Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.\nAbout this article\nCite this article\nLin, X., Wu, M. & Yang, J. Polypoid endometriosis presenting with massive hemorrhagic ascites and diffuse abdominopelvic lesions: a case report and literature review. BMC Women's Health (2026). https://doi.org/10.1186/s12905-026-04970-6\nReceived:\nAccepted:\nPublished:\nDOI: https://doi.org/10.1186/s12905-026-04970-6","source_license":"CC0","license_restricted":false}