If a retroperitoneal occupancy is found, CT examination or biopsy for pathology is needed to further clarify the diagnosis and determine whether the tumor is benign or malignant, and then the corresponding treatment is carried out according to the results of pathological examination. The most common is sarcoma, which is also a kind of malignant tumor and usually requires surgery, which may be followed by combined radiotherapy and chemotherapy. Most patients tend to experience recurrence about six months to a year after surgery, and may require repeated surgical treatment, with a five-year survival rate of about 50%-60% after surgery.