A rare case of hypofractionated endometrial mesenchymal sarcoma with intraventricular growth.

A 44-year-old woman with irregular vaginal bleeding for more than 10 days and a palpable mass in the lower abdomen was the subject of study. Ultrasound suggested a hypoechoic uterine mass, which was considered to be a myoma with mixed echogenicity in the uterine cavity. Scraping showed no abnormal findings. Imaging raised the possibility of tumors of adnexal origin invading the ureter. The patient then underwent an open hysterectomy, bilateral adnexal resection, pelvic lesion resection, and vascular lesion resection. Paraffin section and tissue immunology confirmed a diagnosis of low-grade endometrial mesenchymal sarcoma with vascular cancer thrombosis in the uterus. Tumor tissue was found in the right adnexa, right parametrial lesion, right internal iliac, and inferior vena cava nodes. Postoperatively, the patient received anticoagulation for venous thrombosis of the lower extremities, followed by chemotherapy. Currently, two years later, the patient is in good health and the tumor has not recurred. This metastatic ESS extended from the iliac and ovarian veins to the inferior vena cava, invading the vessels. It is particularly important to remove the lesion as completely as possible in patients with ESS involving the vessels. Furthermore, a close long-term follow-up evaluation is also essential due to the high recurrence rate of ESS.