What is osteosarcoma?

From the Guidelines

Osteosarcoma is a type of bone cancer that originates in the bone tissue, typically in the metaphysis of long bones, and is characterized by the production of immature bone or osteoid tissue.

Key Characteristics of Osteosarcoma

• It is the most common primary malignant bone tumor in children and young adults, with a median age at diagnosis of 20 years 1
• The incidence is higher in adolescents, with a male to female ratio of 1.4:1 1
• Osteosarcoma usually arises in the metaphysis of a long bone, most commonly around the knee, but can also occur in the axial skeleton and craniofacial bones, particularly in adults 1
• It is a high-grade malignancy, with conventional osteosarcoma accounting for 75-90% of all osteosarcomas, and is characterized by the production of immature bone or osteoid tissue 1
• Risk factors for the occurrence of osteosarcoma include previous radiation therapy, Paget’s disease of bone, and germ-line abnormalities such as Li-Fraumeni syndrome, Werner syndrome, and hereditary retinoblastoma 1

Subtypes of Osteosarcoma

• Conventional osteosarcoma: a high-grade malignancy that accounts for 75-90% of all osteosarcomas 1
• Low-grade central and parosteal osteosarcoma: low-grade malignancies that are less common than conventional osteosarcoma 1
• Periosteal osteosarcoma: an intermediate-grade chondroblastic osteosarcoma that is less common than conventional osteosarcoma 1
• Other subtypes, such as telangiectatic, small cell, and high-grade surface osteosarcoma, are less common and have distinct characteristics 1

Diagnosis and Treatment

• Diagnosis is typically made through a combination of imaging studies, biopsy, and histological examination 1
• Treatment usually involves a combination of chemotherapy and surgery, with the goal of achieving complete resection with negative margins 1
• Chemotherapy agents such as doxorubicin, cisplatin, and high-dose methotrexate are commonly used in the treatment of osteosarcoma 1

From the Research

Definition and Overview of Osteosarcoma

• Osteosarcoma (OS) is the most common primary malignancy of bone, characterized by a high degree of malignancy, strong invasiveness, and rapid disease progression 2, 3, 4, 5, 6.
• It is a highly heterogeneous disease in both its origins and manifestations, with unclear and controversial etiology 2, 3, 4.

Clinical Characteristics and Diagnosis

• Osteosarcoma is characterized by a high risk of bone and lung metastases, with a 5-year survival rate around 70% in the absence of metastases and 30% if metastases are detected at the time of diagnosis 4.
• Noninvasive diagnostic methods include serum markers like alkaline phosphatase and various imaging techniques, but biopsy and microscopic examination are required to confirm the diagnosis 2.
• The disease has a bimodal distribution pattern, with incidence peaks in the second decade of life and in late adulthood 6.

Treatment and Prognosis

• The current standard of care combines surgical and chemotherapeutic techniques, with experimental biologics and small molecules in development and some in clinical trial phases 2, 3, 4.
• Complete surgical resection of all sites of disease remains essential to survival, and patients unable to achieve complete remission have a poor prognosis 5.
• The role of second-line chemotherapy is not clear, and innovative therapeutic approaches may be considered for patients with multiple sites of disease not amenable to complete surgical resection 5.