The most valuable auxiliary examination for osteosarcoma

The most common symptom of osteosarcoma in the early stage is local pain or redness and swelling of the bones. If you find these abnormal symptoms, you must go to the hospital for examination and treatment as soon as possible. Many osteosarcoma patients want to know what tests are needed to diagnose osteosarcoma before seeing a doctor. So what are the most valuable auxiliary examinations for osteosarcoma? Today I will give you a detailed introduction.

1. Clinical examination

1) Pain: caused by the traction of the periosteum. Characteristics: mild to severe; intermittent to continuous; pain at night; pain at rest.

2) Lumps: There may be local lumps with varying hardness. The affected area may have increased skin temperature and venous distension.

3) Functional impairment: limited joint movement.

4) Pathological fracture

5) Cachexia symptoms such as anemia, weight loss, and loss of appetite.

2. Imaging examination

X-rays show bone cortical destruction and irregular new bone. In long tubular bones, it often occurs in the metaphysis. CT can show the bone shape and the internal process of the tumor. After enhancement, it can show the blood supply of the tumor, the relationship between the tumor and the blood vessels, and the range in the bone and soft tissue. MRI can clearly show the soft tissue and is very useful for preoperative planning. It can show the extent of tumor invasion in soft tissue and the extent of invasion in the bone marrow cavity, and find skip lesions. The accuracy of the tumor range determined by CT or MRI has been confirmed by surgical resection specimens, so CT or MRI is a necessary means of imaging examination for osteosarcoma. CT can better show the boundaries of cortical destruction and three-dimensional anatomy. Compared with CT, MRI has more advantages in showing tumor soft tissue invasion, and can accurately show the relationship between the tumor and adjacent muscles, subcutaneous fat, joints, and major neurovascular bundles. In addition, MRI can well show the medullary cavity conditions at the distal and proximal ends of the lesion, and find out whether there is skip metastasis. In some cases, digital subtraction angiography (DSA) can also be selected to clarify the relationship between blood vessels and tumors.

3. Laboratory examination

Laboratory tests such as lactate dehydrogenase and alkaline phosphatase are related to the diagnosis and prognosis of osteosarcoma and should be performed before patients receive neoadjuvant chemotherapy. Blood routine and liver and kidney function should be monitored during chemotherapy. It should be noted that these laboratory tests should be reviewed regularly during treatment and follow-up.

4. Pathological examination

The histological manifestations meet the definition of osteosarcoma, which is a highly malignant tumor originating in the medullary cavity, and the tumor cells can produce bone-like tissue. This definition explains two issues: first, the tumor originates in the medullary cavity and is a highly malignant tumor; second, the tumor cells can produce bone-like tissue, regardless of the amount.

The diagnostic examinations that all patients suspected of osteosarcoma should undergo should include: physical examination, imaging examination of the primary lesion (plain X-ray, local MRI or enhanced CT scan), bone scan, chest imaging examination (chest CT is the preferred imaging examination method for detecting lung metastasis), laboratory tests (blood routine, lactate dehydrogenase, alkaline phosphatase), and then biopsy to obtain histological diagnosis, and finally complete the staging diagnosis of osteosarcoma.