1 临床资料 患者,男,38岁。1981年头顶部头皮内有一软组织肿块,较韧。1991年肿块逐渐长大,压之稍痛,当时拍片见头皮内均匀软组织肿块,颅骨完整。手术切除,病理为毛母质瘤。时隔半年后感觉手术区疼痛,又长出软组织肿块。即行拍片,见颅骨左侧巨大骨质缺损,边界较清楚。边缘不规则,病变区内有少 1 Clinical data Patient, male, 38 years old. In 1981, there was a soft tissue mass in the scalp at the top of the head, which was tough. In 1991, the lumps gradually grew up and the pain was slight. At that time, the scalp showed uniform soft tissue masses and the skull was intact. Surgical resection, pathology of hairy tumors. After a lapse of six months, she felt pain in the operating area and grew a soft tissue mass. That is to say, the film shows a huge bone defect on the left side of the skull with a clear boundary. Irregular edges, few in the lesion area