Diagnostic and differential methods for osteosarcoma

When it comes to osteosarcoma, you may know very little about it, because its early symptoms are not obvious, resulting in most patients having metastasized once they are examined. So how is it identified and judged during the examination? Let's learn about the diagnosis and identification methods of osteosarcoma.

Diagnostic methods:

1. Osteosarcoma is common in adolescents aged 15 to 25 years old, and is prone to occur in the epiphyseal ends of the long bones of the limbs. It is most common above and below the knee joint.

2. The main symptom of osteosarcoma is local pain, which is intermittent dull pain at first and quickly turns into continuous severe pain, especially at night.

3. Osteosarcoma patients have high local skin temperature, swollen veins, rapidly growing tumors, tenderness, tremors and vascular murmurs, pathological fractures, and joint dysfunction.

4. Systemic toxic reactions, loss of appetite, weight loss, and finally exhaustion and cachexia.

5. Anemia, increased white blood cell count, erythrocyte sedimentation rate, and increased alkaline phosphatase.

6. Characteristic manifestations of X-ray films.

7. Pathological examination can confirm the diagnosis.

Identification method:

1. Bone metastasis: Most patients with bone metastasis have a history of primary cancer. Metastatic cancer usually occurs in middle-aged and elderly people, which is different from osteosarcoma, which is more common in adolescents. Differentiation from osteosarcoma mainly depends on the age of onset, site of onset and imaging characteristics, and the final diagnosis requires pathological examination.

2. Chondrosarcoma: It occurs at an older age and is more likely to occur in the epiphysis of flat bones or long bones. It presents as irregular osteolytic destruction with unclear boundaries, many calcification shadows, and soft tissue masses around it. Under the microscope, the chondrocytes are lobed, the cells are evenly distributed, the nuclei are hypertrophic, binucleated cells are often seen, and irregular giant chondrocytes are occasionally seen. The key points to distinguish between the two are that chondrosarcoma occurs at an older age, there is no tumor bone in the lesion, periosteal reaction is rare, and pathological examination shows that there is no bone-like matrix in the tumor.

3. Fibrosarcoma: Fibrosarcoma is a primary malignant tumor originating from fibroblasts. It is common in people aged 30 to 50 years old. Intraosseous fibrosarcoma presents with gradually increasing pain. X-rays show penetrating destruction areas with reduced density. Pathological examination shows that its main cytological feature is composed of spindle cells of uniform size and shape. The nucleus is deeply stained, with almost no cytoplasm, and the cell membrane is not obvious or absent. The cells are separated by collagen fibers and intertwined, forming a "herring bone" shape. The key points to distinguish between the two are that fibrosarcoma occurs at an older age, there is no tumor bone in the lesion, periosteal reaction is rare, and pathological examination shows that there is no bone-like matrix in the tumor.

4. Osteofibroma: The disease lasts a long time, with no signs of malignant transformation. The lesions are mainly fibrous tissue hyperplasia and bone sclerosis. X-rays show that the lesions do not destroy the bone cortex, but only cause the bone cortex to expand and thin. There is no periosteal reaction.

5. Myositis ossificans: Sometimes it is similar to osteosarcoma. CT and MRI can clearly show that there is no bone destruction in the bone marrow cavity and cortical bone, while osteosarcoma often has bone destruction.