Osteosarcoma Diagnostic Methods: In clinical practice, once osteosarcoma is suspected in a patient, the diagnostic approach, as per the Chinese Cancer Treatment Guidelines, requires a combination of clinical symptoms, radiological data, and pathology. Only through the integration of these three elements can a definitive diagnosis of osteosarcoma be established. Reliance solely on pathology, or exclusively on radiologic examination or clinical examination, can lead to biased results. Given that immediate treatment is crucial upon the discovery of osteosarcoma, and considering the severe implications of treatment costs, patient suffering, and other related issues, it is vital that the diagnosis of osteosarcoma is error-free. To ensure absolute certainty, the approach should involve clinical symptoms supplemented by necessary auxiliary examinations such as X-rays and CT or MRI scans, followed by a diagnostic biopsy for pathological results. This comprehensive combination generally prevents the occurrence of missed or misdiagnoses in patients with osteosarcoma. Therefore, the confirmatory diagnosis of osteosarcoma should not rely solely on one type of examination but should combine clinical assessment with necessary imaging data and pathology to finalize the diagnosis process.