Radiotherapy-Responsive Soft Tissue Sarcomas

Sarcomas with Standard Radiotherapy Indications

• The European Society for Medical Oncology recommends radiotherapy as a standard treatment for intermediate-to-high grade, deep soft tissue sarcomas >5 cm in diameter when combined with surgical resection, which improves local control, though not overall survival 1, 2, 3
• High-grade tumors (G2-3), deep location, >5 cm diameter represent the strongest indication for adjuvant radiotherapy, according to the European Society for Medical Oncology 2, 3, 4
• The National Comprehensive Cancer Network suggests that deep lesions ≤5 cm may be considered for radiotherapy in selected cases 2
• The European Society for Medical Oncology recommends radiotherapy for large or marginally excised low-grade tumors in selected patients 3
• The American College of Surgeons indicates that R1 (microscopically positive) or R2 (grossly positive) margins that cannot be re-excised are an indication for radiotherapy 1, 5, 4

Radiotherapy Dosing and Sequencing

• The American College of Radiology strongly recommends preoperative radiotherapy over postoperative radiotherapy when radiotherapy is indicated, with a standard dose of 50 Gy in 25 fractions delivered over 5 weeks 1, 2, 5
• The European Society for Medical Oncology suggests that preoperative radiotherapy can facilitate surgery by shrinking the tumor 3
• The National Comprehensive Cancer Network recommends a postoperative radiotherapy dose of 50-60 Gy in 1.8-2 Gy fractions, with boosts up to 66 Gy depending on margin status and presentation 1, 2, 5, 4

Definitive Radiotherapy for Unresectable Disease

• The European Society for Medical Oncology recommends definitive radiotherapy alone for unresectable tumors or those requiring mutilating surgery, with a recommended dose of 66 Gy in 33 fractions over 6.5 weeks 3, 5
• The American College of Radiology suggests that outcomes correlate with tumor size, grade, and radiation dose 3

Advanced Radiotherapy Techniques

• The American Society for Radiation Oncology indicates that intensity-modulated radiation therapy (IMRT) and proton beam therapy enhance dose conformation and reduce normal tissue toxicity 3
• The European Society for Medical Oncology recommends proton therapy for spinal and paraspinal bone and soft tissue sarcomas in adults, as well as for children and teenagers to reduce late toxicity 3
• The American Brachytherapy Society suggests that brachytherapy and intraoperative radiation therapy (IORT) are options in selected cases for microscopic residual disease 1, 2

Critical Caveats

• The Society of Surgical Oncology states that compartmental resection of intracompartmental tumors does not require adjuvant radiotherapy 2
• The European Society for Medical Oncology indicates that preoperative radiotherapy increases acute wound healing complications but reduces late toxicity compared to postoperative treatment 3
• The American College of Radiology notes that radiotherapy improves local control but not overall survival in soft tissue sarcomas 1, 4