Response to Central Boost Radiation Therapy in Unresectable Retroperitoneal Sarcoma: A Case Series

Area of Science:

• Radiation Oncology
• Surgical Oncology
• Medical Oncology

Background:

• Optimal treatment for retroperitoneal sarcoma (RPS) is not well-defined.
• Unresectable RPS poses significant treatment challenges.

Purpose of the Study:

• To assess the feasibility of high-dose radiation boost to the central tumor in unresectable RPS.
• To evaluate local tumor response and toxicity of this novel radiation technique.

Main Methods:

• Five patients with unresectable RPS received intensity-modulated radiation therapy (IMRT) with a central boost.
• Doses ranged from 25-45 Gy to the outer tumor and 56-75 Gy to the central tumor (equivalent dose 62.67-87.5 Gy EQD2).
• Techniques included sequential, interdigitated, or simultaneous integrated boost (SIB) to spare adjacent organs.

Main Results:

• Median survival post-radiation therapy was 30 months.
• Three out of five patients achieved clinically stable local disease.
• No patients experienced clinically significant radiation toxicity.

Conclusions:

• High-dose central boost radiation is a well-tolerated and feasible treatment for unresectable RPS.
• Excellent local tumor control was observed.
• Effective systemic therapy is crucial for managing metastatic disease in these patients.