Key Clinical MessageUterine artery embolization (UAE) is generally performed for benign uterine conditions but is not recognized as a therapeutic option for endometrial cancer. We report a case in which UAE successfully achieved hemostasis for severe bleeding and unexpectedly resulted in complete tumor necrosis. This case suggests that, in selected patients—such as those requiring urgent bleeding control or those who are poor surgical candidates—targeted embolization of dominant tumor-feeding arteries may provide not only hemostasis but also potential tumor control.AbstractUterine artery embolization (UAE) is generally performed for benign conditions and is not used as a treatment for malignant tumors. We report a case of endometrial cancer in which UAE was performed for hemostasis and resulted in complete tumor necrosis.A 46-year-old nulliparous woman presented with abnormal genital bleeding, which worsened after endometrial biopsy. Imaging revealed a large intrauterine mass with active bleeding and severe anemia. UAE was performed to control bleeding prior to definitive diagnosis. Postprocedural MRI showed loss of tumor enhancement. Based on previous biopsy findings, high-grade adenocarcinoma was suspected, and radical surgery was performed one month later. Pathological examination demonstrated complete tumor necrosis, and the patient was diagnosed with stage IA endometrial carcinoma (endometrioid carcinoma G2 or serous carcinoma, pT1aN0M0). Adjuvant chemotherapy was administered, and no recurrence has been observed for 18 months.While UAE is typically used as palliative hemostasis for gynecologic malignancies, this case suggests that selective embolization of the dominant feeding arteries may offer potential tumor control when standard surgical treatment is challenging.Keywordsabnormal uterine bleeding; endometrial cancer; uterine artery embolization; tumor necrosisIntroductionTranscatheter arterial embolization is an established treatment modality for several malignant tumors, including hepatocellular carcinoma and specific brain tumors. In gynecology, however, uterine artery embolization (UAE) is primarily performed for benign conditions such as uterine fibroids or adenomyosis and is not considered a standard treatment for uterine malignancies. We report a rare case of endometrial cancer in which UAE, performed as a hemostatic intervention for severe bleeding, resulted in complete tumor necrosis.Case History/ExaminationA 46-year-old nulliparous woman with no notable medical or family history visited a previous physician for abnormal uterine bleeding and underwent endometrial biopsy. Two days later, genital bleeding increased, and she was transferred to our hospital. On admission, speculum examination revealed continuous bleeding from the external cervical os. Transvaginal ultrasonography showed a mass measuring 78 × 51 mm within the uterine cavity, and laboratory testing demonstrated anemia with hemoglobin 8.4 g/dL. Contrast-enhanced abdominal CT performed to identify the bleeding source revealed contrast extravasation into the uterine cavity (Figure 1-1, 1-2). Because malignancy could not be ruled out and definitive diagnosis was required before determining surgical management, we selected UAE as a temporizing measure rather than immediate hysterectomy.Uterine arteriography showed no active extravasation but revealed bilateral uterine artery enlargement(Figure 1-3, 1-4). Selective UAE was therefore performed on both uterine arteries using gelatin sponge particles. Hemostasis was achieved, and her anemia improved following transfusion of four units of red blood cells.On postoperative day 4, the patient developed fever and elevated inflammatory markers, raising concern for tumor necrosis or bacterial infection. As no laboratory findings suggested tumor lysis syndrome, she was treated with antibiotics, resulting in defervescence and improvement of inflammation. Contrast-enhanced MRI performed two days after UAE showed no enhancement in the intrauterine tumor or fibroid-like mass (Figure 1-5), indicating successful embolization. Although tumor assessment was challenging due to lack of enhancement, myometrial invasion appeared to be less than one-half based on myometrial contrast patterns. Chest and abdominal CT revealed no distant metastases or lymph node enlargement.Differential DiagnosisBased on clinical presentation and imaging findings, the differential diagnosis included endometrial carcinoma, submucosal leiomyoma with secondary bleeding, and uterine sarcoma. Given the persistent bleeding and imaging findings suggestive of malignancy, endometrial cancer was considered the most likely diagnosis.Outcome and Follow-upHistopathology from the previous biopsy suggested either grade 2 endometrioid carcinoma or high-grade serous carcinoma (Figure 2-1). Based on these findings, the tumor was clinically considered endometrial carcinoma stage IA. One month after UAE, the patient underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, pelvic and para-aortic lymphadenectomy, and partial omentectomy. Peritoneal cytology was negative. On permanent pathology, all tumor tissue was completely necrotic, leaving no viable tumor cells for histologic evaluation. Even when considering all necrotic tissue as tumor, myometrial invasion depth was estimated to be less than one-half (Figure 2-2 to 2-5). The final diagnosis was endometrial carcinoma (endometrioid carcinoma G2 or serous carcinoma, pT1aN0M0), stage IA.　As she was considered to have an intermediate- to high-risk profile for recurrence, adjuvant chemotherapy was administered. She has remained recurrence-free to date.DiscussionUterine artery embolization (UAE) is widely used in gynecology for the management of benign uterine disorders, including fibroids and adenomyosis, and as a palliative intervention for refractory bleeding in advanced malignant diseases[1]. However, its application in early-stage endometrial cancer has not been documented, and it is not considered part of standard oncologic management. Patients presenting with acute, heavy bleeding from a uterine tumor may require urgent hemostatic intervention. Emergency hysterectomy is sometimes performed in such settings, and several reports describe massive bleeding secondary to endometrial cancer leading to emergent surgical removal of the uterus[2,3]. Nonetheless, proceeding directly to hysterectomy without adequate imaging or histologic confirmation may risk suboptimal oncologic staging or incomplete surgery. In the present case, given the possibility of malignancy and the absence of a definitive diagnosis at presentation, UAE was selected as a temporizing measure to control bleeding safely until appropriate evaluation and definitive surgery could be performed. Previous studies have shown that embolization can achieve effective hemostasis in cervical cancer, where the uterine arteries represent the predominant blood supply to the tumor. For example, embolization in women with advanced cervical cancer has been associated with successful bleeding control in a significant proportion of cases, with some patients maintaining temporary disease stability[4]. By contrast, the efficacy of embolization in endometrial cancer appears limited, and available reports have largely involved advanced or recurrent disease, often with poor clinical outcomes[5]. One important reason for these differences lies in the vascular anatomy of the uterus. While the cervix is supplied mainly by branches of the uterine arteries, the uterine body has a more complex vascular network with notable collateral circulation from the ovarian arteries. Razavi et al. described an angiographic classification of utero-ovarian collateralization, demonstrating that these collateral pathways influence the success of embolization in uterine fibroids[6]. Therefore, the therapeutic effect of UAE for endometrial cancer likely depends on whether the uterine arteries represent the dominant feeding vessels. In our case, preprocedural CT demonstrated marked enlargement of the uterine arteries, particularly on the right, while the ovarian arteries were not dilated although ovarian artery angiography was not performed during uterine artery embolization,. Selective embolization of the uterine arteries alone achieved complete tumor necrosis, as confirmed by postoperative pathology. This finding supports the notion that, in selected patients, the uterine arteries may serve as the primary blood supply to the tumor, making embolization an effective adjunctive or temporizing intervention. In contrast, the uterine cervix is reported to be supplied predominantly by branches of the uterine arteries, suggesting that uterine artery embolization may achieve more reliable hemostatic and therapeutic effects in cervical cancer[7]. Based on these considerations, unlike uterine fibroids—where preservation of ovarian function is important endometrial cancer may potentially benefit from embolization if the dominant blood supply to the uterus is carefully evaluated, including selective uterine artery embolization and, when appropriate, combined ovarian artery embolization. In a study by Jackie et al., the incidence of newly diagnosed gynecologic malignancies within three years after uterine artery embolization was approximately 0.2% among women with no prior history of gynecologic cancer. Because some of these patients had not undergone preprocedural endometrial sampling, the possibility of preexisting microscopic malignancy cannot be excluded; however, if malignancy developed after UAE, this finding suggests that uterine artery embolization alone cannot serve as a substitute for definitive surgical treatment[8]. Our case also highlights an important limitation: UAE may cause extensive tumor necrosis, rendering subsequent histopathologic evaluation difficult or impossible. In the present patient, all tumor tissues were completely necrotic at the time of hysterectomy, and no viable carcinoma cells remained for definitive histologic classification. Although clinical management was not adversely affected, this raises concerns for cases in which tumor grade, histologic subtype, or lymphovascular invasion would influence treatment decisions. Therefore, when malignancy is suspected, obtaining tissue diagnosis—preferably by endometrial biopsy or hysteroscopic sampling—before performing UAE is strongly advisable. Early histologic confirmation allows accurate preoperative staging and prevents diagnostic uncertainty that may arise when only necrotic tissue is available after embolization. Despite these limitations, UAE may play a useful role in selected clinical situations. Elderly patients or those with significant comorbidities may not tolerate immediate surgery, and UAE can provide rapid hemostasis while potentially suppressing tumor viability. Moreover, in scenarios requiring urgent control of life-threatening bleeding, UAE offers a minimally invasive alternative with lower procedural risk compared with emergent hysterectomy. Current guidelines for endometrial cancer suggest radiation therapy as an alternative for patients unable to undergo surgery. UAE may represent an additional option in such patients by providing immediate bleeding control and possibly short-term tumor control, as illustrated by this case.In summary, while not established as a treatment for endometrial cancer, UAE may have therapeutic potential when the dominant tumor blood supply originates from the uterine arteries. At the same time, clinicians should be aware that embolization may compromise pathologic assessment, underscoring the importance of obtaining pre-embolization tissue diagnosis whenever feasible. Although not a standard treatment for endometrial cancer, UAE may provide both hemostatic and potential therapeutic benefits in selected patients. Accurate assessment of tumor blood supply and pre-embolization biopsy are essential to preserve diagnostic accuracy.Ethical ApprovalWritten informed consent was obtained from the patient for publication of this case report and accompanying images.Conflict of InterestThe authors declare no conflicts of interest.Reference1. Das C, Rathinam D, Manchanda S, et al. : Endovascular uterine artery interventions. Indian J Radiol Imaging, 4: 488–495, 2017.2. Srisomboon J, Phongnarisorn C, Suprasert P : Endometrial Cancer Diagnosed in Patients Undergoing Hysterectomy for Benign Gynecologic Conditions. Thai Journal of Obstetrics and Gynaecology, 13 : 29-32, 2001.3. Tsarna E, Kontou L , Tsochrinis A et al. : Emergency Hysterectomy in a Hemodynamically Unstable Patient: A Case of Uterine Leiomyosarcoma. The Cureus Journal of Medical Science, 12 : e11586, 2020.4. Alméciga A, Rodriguez J, Beltrán J, et al. : Emergency Embolization of Pelvic Vessels in Patients With Locally Advanced Cervical Cancer and Massive Vaginal Bleeding: A Case Series in a Latin American Oncological Center. JCO Global Oncology, 6 : 1376-1383, 2020.5. Choi J, Shin J, Chu H : Transcatheter Arterial Embolization for Palliation of Uterine Body Cancer Bleeding. Journal of The Korean Society of Radiology, 84 : 606–614, 2023.6. Razavi MK, Wolanske KA, Hwang GL, et al. : Angiographic Classification of Ovarian Artery-to-Uterine Artery Anastomoses: Initial Observations in Uterine Fibroid Embolization. Radiology, 224 : 707-712, 2002.7. Bereza T, Tomaszewski KA, Walocha J, et al. : Vascular architecture of the human uterine cervix, as assessed in light- and scanning electron microscopy. Folia Morphologia, 71 : 142-147, 2012.8. Bronico JVR, Matthews BJ, Perkins RB, et al. : Incidence of Gynecologic Cancers in Women after Uterine Artery Embolization. J Minim Invasive Gynecology, 28 :1231–1236, 2020.Author contributionYY contributed to patient management, data collection, and drafting of the manuscript.YA, YT, YO, MI participated in clinical management, data interpretation, and manuscript review.HS supervised the clinical course, contributed to interpretation of radiologic and pathologic findings, and critically revised the manuscript.NT and KK contributed to surgical management, pathological evaluation, and manuscript revision.All authors read and approved the final manuscript.Figure LegendsFigure 1Contrast-enhanced computed tomography performed prior to embolization showing active contrast extravasation into the uterine cavity(Arrow) and the presence of an intrauterine tumor(Arrow head,1A). Dilation of the right uterine artery was observed(Arrow, 1B).Figure 2Selective uterine arteriography demonstrating bilateral enlargement of the uterine arteries, before uterine artery embolization(2A;right side 2B;left side).Figure 3.Post-embolization contrast-enhanced pelvic MRI (T1-weighted) showing absence of enhancement in the intrauterine lesion, consistent with treatment effect following uterine artery embolization.Figure 4.Endometrial biopsy obtained at the referring institution demonstrating features suggestive of high-grade adenocarcinoma (endometrioid carcinoma G2 or serous carcinoma).Figure 5Gross pathological specimen from hysterectomy showing complete tumor necrosis within the uterine cavity(5A). Low-power view (loupe) of the resected specimen showing widespread coagulative necrosis throughout the tumor(5B). Intermediate-power microscopic view (×20) demonstrating necrotic tissue without viable tumor cells(5C). High-power microscopic view (×200) confirming complete tumor necrosis and absence of recognizable carcinoma cells(5D).