患者男,41岁。肛门旁左后侧渐生长的无痛性核桃大肿块半年,近半个月来突然生长较快,无任何不适,大便正常。检查:肛门与尾骨间旁左约有5×7cm半球形肿块,皮肤色泽正常,表面不平滑,质地柔韧,周围界限尚清,基底固定。指肛检无异常。以良性肿瘤局麻下手术切除,术中见肿物无包膜,像肌肉组织,便色泽较暗,位于皮下组织,部分易分离,基底部深埋于臀部肌肉组织,极易出血,切除后加压包扎,伤口一期愈合。病理报告横纹肌肉瘤。 Male patient, 41 years old. The painless walnut mass that grows gradually to the left and the back of the anus grows for half a year. In the past half month, it suddenly grows faster, without any discomfort, and the stool is normal. Examination: There is a 5×7cm hemispherical mass around the left and the right between the anus and the coccyx. The skin has normal color, the surface is not smooth, and the texture is flexible. The boundary is still clear and the base is fixed. Refers to the anal examination without exception. With benign tumors under local anesthesia for surgical resection, the tumor was seen in the operation without a capsule, like muscle tissue, it was dark in color, located in the subcutaneous tissue, some easily separated, the base is deeply buried in the gluteal muscle tissue, easily bleeding, after resection With pressure dressing, the wound healed for the first time. Pathology reports rhabdomyosarcoma.