Definitive particle therapy using protons or carbon ions for dedifferentiated liposarcoma

Area of Science:

• Oncology
• Radiation Oncology
• Medical Physics

Background:

• Particle therapy is an effective treatment for soft tissue sarcomas.
• Clinical outcomes for definitive particle therapy in dedifferentiated liposarcoma (DDLS) are not well-established.

Purpose of the Study:

• To analyze treatment outcomes of proton and carbon ion particle therapies for DDLS.
• Evaluate the efficacy and safety of particle therapy in DDLS patients.

Main Methods:

• Retrospective analysis of 57 DDLS patients treated with particle therapy (2008-2022).
• Evaluation of local control (LC), progression-free survival (PFS), and overall survival (OS) rates.
• Comparison of outcomes based on prescribed dose and gross tumor volume (GTV).

Main Results:

• 3-year LC, PFS, and OS rates were 73.1%, 44.6%, and 70.6%, respectively.
• Higher prescribed doses (≥72.7 Gy EQD2) correlated with significantly better LC (p=0.04).
• Larger GTV (≥181 cm³) was associated with significantly worse OS (p=0.04).
• Late adverse events occurred in 9% of patients.

Conclusions:

• Particle therapy (proton or carbon ion) is safe and effective for DDLS, offering good OS and LC.
• Higher doses and smaller tumor volumes may improve outcomes.
• Further studies with larger cohorts and longer follow-up are warranted.