Rare Presentation of Retroperitoneal Leiomyosarcoma Mimicking a Myoma in a 46-year-old Woman: A Case Report

Abstract Background: Retroperitoneal sarcoma (RPS) are relatively uncommon, constituting only 10 to 15 percent of all soft tissue sarcomas. Case presentation: We share our experience in encountering RPL with vascular and urethral adhesion in the operation room in a 46-year-old woman, whom was scheduled for surgery as a case of leiomyoma.Huge solid retroperitoneal mass (16*12*11 cm) was detected in right broad ligament which was attached to the pelvic floor and seemed to be separated from uterus. Because of a dense adhesion of the tumor to the ureter and vessels tearing of internal iliac vein and ureteral injury occurred during dissection that was repaired. Pathologic examination revealed grade II / III leiomyosarcoma with mitotic rate 12 / 10 HPF, including atypical forms. she candidates for radiation. Conclusion: This case report describes the clinical, imaging, surgical and histopathological findings of retroperitoneal leiomyosarcoma. Due to the rarity of these tumors and the complexity of treatment, evaluation and management should ideally be carried out in a center with multidisciplinary expertise in the treatment of sarcomas.