Design: Case presentation via surgical video

Setting: Academic tertiary care center

Patients or Participants: 67 year old female with history of stage IA grade 1 endometrioid adenocarcinoma of the uterus s/p robotic-assisted hysterectomy, bilateral salpingo-oophorectomy, and sentinel lymph node dissection four years prior. Patient presented with left lower quadrant pain radiating to the back for a couple of months. Her preoperative imaging revealed a new 1.5 x 1.3 cm soft tissue nodule in the medial border of the left psoas muscle.

Interventions: N/A

Measurements and Main Results: Patient underwent a robotic assisted laparoscopic removal of 2.5 cm left retroperitoneal nodule and pelvic washings. There were no surgical complications. Patient was discharged on postoperative day 1. Final pathology of retroperitoneal mass was consistent with leiomyosarcoma arising from a vascular structure

Conclusion: Primary retroperitoneal leiomyosarcoma tumors originating in the blood vessels are extremely rare and can present with nonspecific symptoms such as abdominal pain. Treatment of vascular leiomyosarcomas typically involves surgical resection of the involved vascular segment with negative margins. Performing minimally invasive resection of retroperitoneal nodules is feasible with adequate surgical planning including preoperative imaging and a solid understanding of retroperitoneal anatomy.