Retroperitoneal hemorrhage due to spontaneous rupture of adrenal myelolipoma

Background : A very rare case of retroperitoneal bleeding due to spontaneous rupture of a large adrenal myelolipoma in a 62‐year‐old woman is reported. Methods/Results : She consulted the emergency room of the Nagano Red Cross Hospital with a complaint of sudden left flank pain. A computerized tomography (CT) scan revealed a tumor with areas of fat density and hematoma in the left retroperitoneal space. After her general condition improved, an operation was performed. The tumor strongly adhered to the left kidney and a left nephrectomy with the tumor was curative. Histologic diagnosis was adrenal myelolipoma. No blood transfusion was required. Conclusions : A CT scan is very useful in the pre‐operative diagnosis of adrenal myelolipoma with retroperitoneal hemorrhage. Watch and wait treatments before operation and nephrectomy with adhered tumor are safe and curative.