ABSTRACT
OBJECTIVE: To report a case of GIST type retroperitoneal tumor with spontaneous rupture to the abdominal cavity causing acute abdomen secondary to hemoperitoneum. METHODS/RESULTS: We report the case of an 84 year-old man with history of BPH and chronic atrial fibrillation. He presented to the Emergency Department with diffuse abdominal pain, syncope and accompanying vegetative symptoms. Diagnostic work up showed a 19 cm retroperitoneal mass dependent of the left kidney with active bleeding and secondary hemoperitoneum. Left radical nephrectomy was performed with pathology report of gastrointestinal stromal tumor attached to the renal capsule. CONCLUSIONS: Spontaneous hemoperitoneum is a rare entity and it has various etiologies. It is rarely described in retroperitoneal tumors.