患者女，藏族，25岁，农民，右足踝关节内侧发现一无痛性肿物一年多，近期肿物增大来院治疗。临床及X光片见右胜骨下端内侧踝关节处见4cmX3cm大小的肿物，质硬，不活动，无压痛。病检；肉眼见带皮肤扁圆形肿物一个，大小为4X4X2cm，呈灰白结节状，界限清，切面见肿物中央及大部 The patient female, Tibetan, 25 years old, farmer, found a painless mass on the medial side of the ankle of the right foot for more than a year, and the recent mass enlargement came to the hospital for treatment. In clinical and X-ray films, see a mass of 4cmX3cm in the medial sacroiliac joint at the lower end of the right ostium, which is hard, inactive, and tender. Disease examination; naked eye with a flat round skin tumor, the size of 4X4X2cm, was gray nodules, clear boundaries, cut surface to see the central and most of the tumor