例 1.男性 ,5 5岁。 6个月前自觉上腹部疼痛 ,食欲下降 ,于体检时发现左上腹部有手拳大肿块 ,以腹膜后肿瘤行剖腹探查。术中见肝脏大小、色泽正常 ,无结节。肿物位于腹膜后腹主动脉左侧 ,表面血管丰富 ,呈紫红色 ,有包膜 ,肿物呈圆型 ,为 14ｃｍ× 13ｃｍ× 12ｃｍ ,与降结肠系 Example 1. Male, 5 5 years old. Six months ago, she felt conscious upper abdominal pain and her appetite decreased. During the physical examination, a large lump was found in the left upper abdomen and laparotomy was performed with a retroperitoneal tumor. The liver size, color, and nodules were seen during the operation. The tumor is located on the left side of the retroperitoneal abdominal aorta. The surface vessels are rich in purplish red and enveloped. The tumor is round and is 14cm × 13cm × 12cm.