Osteosarcoma diagnostic reference standard

According to a survey, about 20% of osteosarcoma cases have already metastasized to the lungs when diagnosed. Therefore, early diagnosis is very important for the treatment and prognosis of osteosarcoma. Osteosarcoma is a disease with relatively uncommon symptoms after onset, so early diagnosis is very important. What are the reference standards for the diagnosis of osteosarcoma? Let's take a look at it together.

(1) Blood test

Plasma alkaline phosphatase (AKP) and lactate dehydrogenase (LDH) are moderately to significantly elevated. In most cases, elevated AKP can be observed and is associated with the osteogenic activity of tumor cells, but there is no exact quantitative relationship between the AKP level in tumor tissue and the AKP level in plasma. More important than the diagnostic value of AKP is the significance of this indicator for prognosis. If the tumor is completely removed surgically, AKP can drop to normal levels; if the indicator does not drop to normal levels after surgery, or remains at a high level, it often indicates the presence of tumor metastasis or residual tumor.

(2) Imaging examination

①X-ray examination

②Computed tomography (CT)

③MRI

④ Bone scan

⑤ Angiography

(3) Histological diagnosis

Puncture or incisional biopsy and histopathology are the basis for the diagnosis of osteosarcoma. Pathological diagnosis should be obtained before treatment begins. Relevant training for pathologists should be strengthened. If the diagnosis is difficult, a combined consultation of clinical, imaging and pathology is required for confirmation.

Under the microscope, the histological feature of osteosarcoma is the osteoid matrix produced by malignant spindle cells. The spindle cells must be close to the osteoid matrix, and normal osteoblasts are arranged around the osteoid matrix. Tumor tissue cells are diverse. Tumor cells are spindle-shaped or irregular, with large cell volume, dark nuclei, increased nuclear-cytoplasmic ratio, and nuclear division. The characteristics are tumor cell atypia. The key to pathological diagnosis depends on the presence of osteoid matrix (eosinophilic transparent substance) produced by tumor stromal cells.

The diagnosis of osteosarcoma can be basically established based on clinical data such as medical history, symptoms, signs, laboratory and imaging. The diagnosis of osteosarcoma is based on the results of histopathological examination. The diagnosis is difficult and should be determined by combining clinical, pathological and pathological data.