Osteosarcoma is a primary malignant bone or soft tissue tumor arising from osteogenic mesenchymal cells. There are many subtypes of osteosarcoma: typical osteosarcoma, low-grade malignant intramedullary osteosarcoma, osteosarcoma secondary to Paget’s disease, parosteal osteosarcoma, periosteal osteosarcoma, small cell osteosarcoma, soft tissue osteosarcoma, and capillary dilated osteosarcoma. The age of prevalence is 10 to 20 years old, with more males than females. It occurs mostly in the long bone epiphysis of adolescent patients, such as the distal femur, proximal tibia, proximal humerus and distal radius, sometimes with multicentric onset. Etiology】 The cause is unknown, there are many theories, such as chemical carcinogenesis, viral carcinogenesis, radiation carcinogenesis, etc. Clinical manifestations】 Osteosarcoma has no typical symptoms in the early stage, but only pain in the near joint, often intermittent attacks, intensified after activity, the pain increases after a few weeks and is persistent, local soft tissue masses appear, the masses gradually aggravate, hard to touch, pain is obvious, the increasing masses border is not obvious, local skin temperature increases, superficial venous anger is visible on the skin surface, some patients can occur pathology Fracture. When the tumor involves osteochondral bone, swelling of joint cavity may occur. When the tumor progresses significantly, local lymph node enlargement can be palpated. Patients may develop lung metastasis at an early stage, but the clinical condition may be asymptomatic. X-Ray examination In the early stage, there is dissolution of bone trabeculae in the epiphysis, bone defect may involve the medullary cavity, cancellous bone or bone cortex, and there is consistent density of speckled and massed osteogenesis, and there may be periosteal reaction, generally in the form of laminae or small radiolucencies. With further development of the lesion, bone destruction occurs in the backbone, and periosteal reaction may appear as Codman’s triangle, often with soft tissue swelling and unshaped scattered tumor bone within the soft tissue mass. Some osteosarcomas may be sclerotic and are often referred to as sclerosing osteosarcomas, which are generally of the osteoblast type. Osteosarcomas that are purely osteolytic are often referred to as osteolytic osteosarcomas, which are mostly fibroblastic or chondroblastic. In advanced cases, articular cartilage may be involved. Osteosarcoma often metastasizes to the lung and pleura. Chest radiographs show calcification of metastases in the lung and pleural effusion if the pleura is invaded. 2.Radionuclide scan Typical osteosarcoma shows extensive and high concentration of nuclide, but jumping foci are difficult to identify. 3.CT examination CT can show the specific situation of osteogenesis and destruction, and sometimes can identify the jumping foci. CT examination of osteolytic osteosarcoma can find a small amount of residual bone in the osteolytic area and a small amount of tumor bone in the soft tissue mass; CT examination of osteogenic osteosarcoma can find the erosion and destruction of bone by the tumor in a large amount of dense and elevated tumor bone. 4.MRI examination Sclerosing osteosarcoma shows low signal on T1-weighted image and T2-weighted image, but edema or non-sclerotic area around the tumor shows high signal on T2-weighted image. In chondroblastogenic sarcoma, the cartilage component is high signal on T1 and T2-weighted images. Osteosarcoma with a large number of spindle-shaped fibroblasts shows low to moderate signal on T1-weighted image and moderate to high signal on T2-weighted image. 5.Pathological examination: Hard, white tissue with scattered fish-like or hemorrhagic areas are usually seen. When the tumor is marked preoperatively with tetracycline, it is easier to determine the intramedullary extent, satellite nodes, jumping foci, epiphyseal invasion, and joint invasion. Satellite foci are small and usually need to be visualized below the scope. Isolated satellite foci can be seen within the reaction zone of either low- or highly malignant sarcomas. Satellite foci are not true metastases, but are tiny lesions that invade directly outside the tumor envelope. Sometimes, when it is large enough, it can be seen directly on the gross specimen and on x-ray. What is seen microscopically Typical osteosarcoma has highly malignant cytologic changes with tumorigenic bone formation. The tumorigenic bone is immature, irregular in shape, and not aligned in the direction of stress. Cartilage and/or fibrous differentiated areas are often seen. Differential diagnosis】 1. Chondrosarcoma develops at an older age, usually in the flat bone or long bone epiphysis, with irregular osteolytic destruction, poorly defined borders, with calcified shadows, surrounded by soft tissue masses. Microscopically, chondrocytes are lobulated, with a uniform distribution of cells and hypertrophic nuclei, often with binucleated cells, and occasionally with irregularly shaped giant chondrocytes. The main points of differentiation between the two are the older age of chondrosarcoma, the absence of tumor bone in the lesion, the presence of calcified shadows, the rare periosteal reaction, and the absence of tumor bone in the tumor on pathological examination. Fibrosarcoma is more frequent in 30-50 years old, and the X-ray of fibrosarcoma in bone shows a penetrating eccentric destruction area with reduced density, without tumor bone and calcification. Treatment idea】 90% of the cases are stage II-B tumors, another 5% are stage II-A tumors, and 5% are stage III tumors. For typical osteosarcoma, if its preoperative chemotherapy is effective, extensive bulky resection is feasible. However, if chemotherapy is ineffective, radical resection or amputation should be performed. Distant metastases from osteosarcoma are mostly located in the lungs and, to a lesser extent, in the bone. While distant soft tissue metastases are mostly neglected, lung metastases are often treated by surgical resection. (1) Chemotherapy: The current chemotherapy for osteosarcoma is called neoadjuvant chemotherapy, and the principles include three parts: (1) emphasize the importance of preoperative chemotherapy; (2) examine the necrosis rate of resected tumor; (3) decide the postoperative chemotherapy plan according to the high or low necrosis rate of tumor. The current trend is to use very strong pre-surgical chemotherapy in combination with high doses of methotrexate, cisplatin, isocyclophosphamide and adriamycin. After a short course of chemotherapy for approximately 2 months, surgery can be performed when liver and kidney function is not significantly abnormal and platelets and neutrophils have returned to normal levels. In the few cases where chemotherapy cannot be completed before surgery due to very bulky and rapidly growing tumors, amputation should be performed without delay. After surgical resection, at least one section of the whole tumor specimen should be examined histologically. When the necrosis of tumor cells reaches 90%, it means that the tumor has good sensitivity to chemotherapy, so the same drugs should be continued. The commonly used drugs are methotrexate (MTX), adriamycin (ADM), cisplatin (CDP), vincristine (VCR), isocyclophosphamide (IFO) and so on. All antineoplastic drugs have toxic effects on the body, and the main toxic reactions are liver function damage, digestive system reaction, oral mucosal ulcer, bone marrow suppression, etc. At present, although it is not possible to achieve uniformity in chemotherapy regimens, some principles have gradually been agreed upon. The aim of chemotherapy is to improve the long-term survival of patients and to reduce the incidence of fatal distant metastases. Therefore, the main target of chemotherapy is distant micro-metastases rather than local primary foci, and the concept of simply pursuing resection rate is wrong. (2) Radiotherapy: In some cases, such as patients who refuse amputation can be considered to try radiotherapy. (3) Traditional Chinese medicine treatment: reference can be made to outline the part of traditional Chinese medicine with evidence. Luoyang Orthopedic Hospital of Henan Province has accumulated rich experience in traditional Chinese medicine treatment of bone tumor, and has developed a special formula for the treatment of osteosarcoma, DD Huayan capsule, which is composed of Astragalus, Atractylodes, Bupleurum, Epimedium, Angelica, Paeonia, Rhubarb, Curcuma, Nanxing and Ginger. The treatment principle is to tonify the kidney, strengthen the spleen, soften the firmness and disperse the knots, expel phlegm and break up stasis. Radix Astragali and Atractylodes Macrocephalae strengthen the spleen, elevate the clear and lower the turbidity, so that the essence of water and grain does not produce phlegm but becomes nutrients; Boneset and Epimedium nourish the kidney yang and expel cold phlegm; Angelica and Paeonia lactiflora nourish the blood and promote blood circulation, unblock the qi flow and make the qi flow smooth. Rhubarb invigorates blood and breaks down blood stasis, Curcuma longa softens hardness and disperses knots, Nan Xing and Jiang Huang expel phlegm, this formula both supports the positive and expels the evil. Clinical studies have shown that Huayan capsule has a certain effect on the volume reduction of osteosarcoma, and has a significant effect on relieving pain, improving patients’ quality of life and increasing their survival rate, and can be used as an adjuvant medicine for osteosarcoma. The preliminary experimental study proved that the inhibition rate of solid sarcoma in S180 mice reached 62,5%; it can significantly improve the cellular immune function of S180 tumor-bearing mice and enhance the T-cell response ability; the study on the induction of the regulatory effect on the osteosarcoma cell line U2-OS showed that its effect on the G2/M phase of the tumor cell cycle, the apoptosis rate reached 41,05%, and the immune There was extensive DNA breakage by immunohistochemistry. The indications for limb-preserving surgery are generally considered to be: stage IA, IB, IIA tumors or chemotherapy-sensitive IIb tumors; vascular nerves are not involved and the tumor can be completely removed; limb function after limb-preserving surgery is better than that of prosthesis; local recurrence and metastasis rates after surgery are not higher than those of amputation The limb is not likely to be unequal in length after adult or epiphyseal closure. According to the scope of tumor invasion shown by preoperative MRI, osteotomy is performed at the distal or proximal 4-6 cm of the tumor. After extensive resection of the limb tumor, the following techniques can be reasonably selected to reconstruct the limb function according to the site of the tumor, prognosis, complications and the patient’s age and requirements. (1) Joint fusion: Applicable to osteosarcoma of femur, tibia, humerus and upper and lower ulna, fusion of hip, shoulder, elbow or wrist joint after resection of tumor segment. After resection of the tumor segment, autologous iliac or fibular bone graft, or autologous femoral or tibial condyle reversal is used to fill the bone defect, or allogeneic bone graft corresponding to the defective segment can be used to replace the bone defect. The other end of the joint surface is excised, and the two ends are dovetailed and fixed with a corresponding internal fixation device under pressure. The disadvantage is the loss of joint function, which brings inconvenience to life. (2) Artificial prosthesis replacement: Applicable to osteosarcoma of femur, tibia, upper and lower humerus and upper ulna, age above 8 years. After the amputation of malignant tumors of the limbs, replacement with artificial prosthesis has become the most common method to save the limbs. The biggest advantage is that the function is recovered quickly, and the patient can walk with weight in 4-6 weeks in the lower limb. The disadvantage is the late loosening of the prosthesis (5-year loosening rate 20%-25%), fracture of the prosthesis, infection of the prosthesis and other complications. (3) Allograft osteoarthroplasty: for osteosarcoma of the femur, upper and lower humerus and upper tibia and ulna (Figure 9-2-9). The advantage is that it restores bone continuity, reconstructs the joint structure, and provides a soft tissue attachment site. The disadvantages are immune rejection, the need to avoid weight bearing for a long time and delayed functional recovery. The main complications are deep infection, bone resorption, bone non-healing, joint surface collapse, loosening and fracture of internal fixation, advanced joint degeneration and collapse, and joint instability. (4) Composite grafting of allograft bone and artificial prosthesis: adapted for reconstruction of hip and knee joints after osteosarcoma amputation at the upper and lower femur (Figure 9-2-10). Allograft hemiarthroplasty has more complications such as rejection, non-healing, re-fracture, joint collapse, instability, etc. In order to avoid the disadvantages of allograft hemiarthroplasty, a composite graft of allograft bone and artificial prosthesis is used instead. The advantage is that allograft bone restores bone continuity, adjusts length, and provides ligament attachment. The prosthesis provides a mobile joint. After the allograft bone heals with the host bone, the stress passes through the prosthesis to the host bone, reducing the rate of loosening. Disadvantages: loosening and fracture of the prosthesis, allograft bone rejection reaction, etc. (5) Autologous bone grafting with blood vessels: it is suitable for those who resect and reconstruct tumors of the humeral stem, femoral stem, tibial stem, or resect and reconstruct osteosarcoma of the distal radius and upper humerus to reconstruct the shoulder and wrist joints. At present, autologous fibula and iliac bone grafts with blood vessels are commonly used, such as anastomotic long-segment fibula hemiarthroplasty to replace the upper humeral defect and to replace the distal radial bone defect, and anastomotic long-segment fibula to replace the lower femoral or upper tibial bone defect for knee joint fusion. The advantage is that blood circulation is established immediately, which allows some osteoblasts to survive, preserving osteogenic capacity, early formation of bone tissue, rapid bone healing, and high success rate. The disadvantage is that the bone with blood vessels needs to be taken and the blood vessels have to be anastomosed. (6) Tumor bone inactivation and replantation: It is suitable for osteosarcoma of the extremities where bone destruction is not serious and bone strength is not significantly damaged. Microwave heating inactivation, alcohol inactivation, high pressure and high temperature inactivation are often used. The advantage is that the continuity and original shape of the backbone can be maintained. The disadvantage is that it is often complicated by fracture, plate and screw breakage, bone non-healing and poor joint movement. (7) Rotational plasty: It is suitable for stage IIB osteosarcoma of the middle and lower femur which has no neurovascular involvement in IA, IB, IIA or surgical stage. After the tumor segment is amputated, the thigh is replaced by the calf with good tissue structure, and the knee joint is replaced by the ankle joint rotated 180 degrees backward, and the calf prosthesis is fitted after surgery. (2) Amputation surgery: If there is extensive local infiltration, even the nerves and blood vessels have been invaded by the tumor, or there is distant metastasis, extensive transosseous amputation or radical joint dissection will be performed.