Abstract
Retroperitoneal sarcoma (RPS) is a rare and heterogeneous tumor. A percutaneous core needle biopsy (PCNB) is required for obtaining a histological diagnosis of the condition and for planning the therapy. Surgery is the standard of care for RPS; it is a standardized procedure, and it should be performed in a referral sarcoma center. Sarcoma surgery is rarely performed on an urgent or emergent basis. In this report, we describe a case of a retroperitoneal leiomyosarcoma that presented with spontaneous rupture and hemoperitoneum, which required surgical treatment in an urgent manner. To our knowledge, this is the first case of hemoperitoneum due to RPS rupture to be reported in the literature.