Chest wall infiltration: Chest wall tumors generally refer to tumors of the deep soft and skeletal tissues of the chest wall. Chest wall tumors can be divided into two categories: primary and secondary. Secondary chest wall tumors are mostly caused by the metastasis of malignant tumors from other parts of the body to chest wall tissues, or direct infiltration of malignant tumors of lung or pleura adjacent to the chest wall. Primary chest wall tumors are rare, accounting for about 5-10% of the primary tumors in the whole body. 80% of them occur in the ribs, most of them are benign, and about 20% occur in the sternum, while tumors in the sternum are more malignant. Rib tumors are usually found in the anterior and lateral chest walls, and are less common in the posterior chest wall. What are the examination methods of soft tissue tumor? X-ray examination X-ray examination can help to further understand the scope, transparency and relationship between soft tissue tumor and adjacent bone. If the boundary is clear, it often indicates benign tumor; if the boundary is clear and calcification is seen, it indicates highly malignant sarcoma, which mostly occurs in synovial sarcoma, rhabdomyosarcoma and so on. This method can check the volume range of the tumor, the boundary of the envelope and the echogenicity of the tumor tissue inside the tumor body, so as to distinguish benign or malignant. Malignant tumors are large with unclear borders and blurred echogenicity, such as rhabdomyosarcoma, synovial leiomyosarcoma and malignant fibrous histiocytoma. Ultrasonography can also guide the needle aspiration cytology of deep tumors. This examination method is indeed an economic, convenient and non-destructive method for human body. CT examination Because CT has the characteristics of density resolution and spatial resolution for soft tissue tumors, it is also a common method to diagnose soft tissue tumors in recent years. MRI examination can make up for the shortage of X-ray CT in diagnosing soft tissue tumor, which shows the level of various tissues and the whole range of tumor from longitudinal section, and it is a good basis for making treatment plan. V. Pathological examination 1. Cytological examination: It is a simple, fast and accurate pathological examination method. It is most suitable for the following cases: ① soft tissue tumor that has broken down, using the collection method of smear or scraping to obtain cells and microscopic examination to confirm the diagnosis; ② soft tissue sarcoma caused by thoracoabdominal fluid, the fresh specimen must be taken, immediately centrifuged and concentrated, and then smear; ③ puncture smear examination is suitable for tumor that is larger and deeper and intended for radiotherapy or chemotherapy, and also for metastatic lesions and recurrent lesions. 2.Clamp biopsy: When soft tissue tumor has broken down and cytological smear cannot confirm the diagnosis, clamp biopsy can be done. 3.Excisional biopsy: this method is mostly adopted in surgery. If a large limb tumor needs to be amputated, an excisional biopsy can be done before amputation in order to get an exact pathological diagnosis. If the tumor is located in chest, abdomen or retroperitoneum, it cannot be completely removed, so it can be excised and biopsied, and radiotherapy or chemotherapy can be used after the diagnosis is confirmed. 4.Excisional biopsy: It is suitable for small soft tissue tumor, which can be sent to pathological examination together with the whole piece of normal tissues around the tumor.