Is there a role for radiotherapy in osteogenic sarcoma?

From the Guidelines

Radiotherapy has a limited but crucial role in the management of osteogenic sarcoma, primarily used when complete surgical resection is not possible or for palliation of symptoms in metastatic disease, as stated in the most recent guidelines 1.

Key Points to Consider

• The primary treatment approach for osteogenic sarcoma involves chemotherapy and surgery, with radiotherapy playing a supportive role in specific scenarios.
• According to the UK guidelines for the management of bone sarcomas 1, adjuvant radiotherapy is not recommended routinely after surgery, but it can be used to achieve local tumor control if surgical removal is not possible.
• Radiotherapy may be employed for palliation of symptoms in metastatic disease, particularly for painful bone metastases.
• Modern radiation therapy techniques, such as intensity-modulated radiation therapy (IMRT), stereotactic body radiation therapy (SBRT), or proton therapy, allow for higher doses to the tumor while sparing surrounding normal tissues.
• The combination of radiotherapy with radiosensitizing chemotherapy agents may enhance treatment efficacy in selected cases, as suggested by previous studies 1.

Clinical Scenarios for Radiotherapy

• Inoperable tumors or cases where complete surgical resection is not possible.
• Local control after incomplete resection.
• Palliation of symptoms in metastatic disease, particularly for painful bone metastases.

Important Considerations

• Osteogenic sarcoma is considered relatively radioresistant, requiring higher doses (60-70 Gy) for definitive treatment, which explains why surgery remains the preferred local therapy when feasible.
• The role of radiotherapy should be considered as part of a multidisciplinary approach rather than as a standalone curative treatment for osteogenic sarcoma.
• The most recent and highest quality study 1 provides the basis for current recommendations, emphasizing the importance of a multidisciplinary approach in the management of osteogenic sarcoma.

From the Research

Role of Radiotherapy in Osteogenic Sarcoma

• The use of radiotherapy in osteogenic sarcoma is limited due to the rarity of the tumor and the high local control rate achieved with surgery 2.
• However, radiotherapy can be an important option for local treatment of unresectable tumors, following intralesional resection, or as palliation of symptomatic metastases 2.
• A study published in 1985 demonstrated that combined modality treatment, including hypofractionated irradiation, intra-arterial infusion of radiosensitizer, and adjuvant systemic chemotherapy, can achieve local control in patients with unresectable osteogenic sarcoma 3.
• Another study published in 2009 analyzed the experience with radiotherapy in the local treatment of osteosarcoma and found that the combination of surgery, radiotherapy, and chemotherapy can be curative 2.
• The consistent use of full-dose chemotherapy is of importance for the response to radiotherapy, and prognostic factors for survival and local control include indication for RT, RT plus surgery vs. RT alone, and tumor location 2.

Indications for Radiotherapy

• Radiotherapy can be used as a primary treatment for osteogenic sarcoma in cases where surgery is not possible due to location or patient refusal 3.
• It can also be used as an adjuvant treatment following surgery to reduce the risk of local recurrence 2.
• In cases of metastatic disease, radiotherapy can be used for palliation of symptomatic metastases 2.

Efficacy of Radiotherapy

• The efficacy of radiotherapy in osteogenic sarcoma is limited, with a local control rate of 30% reported in one study 2.
• However, the combination of surgery and radiotherapy can improve local control rates, with a significant difference in local control rates between combined surgery and RT versus RT alone (48% vs. 22%, p=0.002) 2.
• The use of radiosensitizers, such as 5'-bromodeoxyuridine (BUdR), can enhance the efficacy of radiotherapy 3.