© 2018 Elsevier Inc. A 32 year-old nulligravid woman with a uterine mass underwent exploratory laparotomy with myomectomy. Final pathology revealed a low-grade endometrial stromal sarcoma (ESS) with positive margins. She subsequently underwent definitive robotic hysterectomy and bilateral salpingectomy with ovarian preservation. She was diagnosed with a stage IB low-grade ESS. She is currently undergoing observation. Discussion of classification, surgical options, and adjuvant therapy is presented.