Palliative Chemotherapy of Recurrent Low-grade Endometrial Stromal Sarcoma with Intracaval and Intracardiac Extension

Abstract Low-grade endometrial stromal sarcoma (LG-ESS) is a rare, indolent subtype of uterine malignancy, typically manifesting in women aged 40–55 years. Despite a generally favorable prognosis, there is a significant risk of late recurrence, often presenting with atypical uterine bleeding (AUB) and pelvic pain. This case report describes a 31-year-old Iranian woman, initially presenting with AUB and treated for presumed benign conditions, who was later diagnosed with LG-ESS following surgical intervention. A year postdiagnosis, the patient experienced recurrence with extensive intravascular and intracardiac tumor thrombosis involving the inferior vena cava and cardiac chambers, a rare and challenging complication. Surgical options were deemed too risky due to the tumor’s extent; thus, palliative chemotherapy was initiated. The treatment included doxorubicin and ifosfamide, supported by mesna and pegfilgrastim, and enoxaparin for thrombosis management. Follow-up imaging showed partial regression of the tumor mass. This case underscores the diagnostic challenges and management complexities associated with recurrent LG-ESS, especially with unusual metastatic patterns, emphasizing the need for vigilant long-term follow-up and a personalized multidisciplinary approach to treatment.