Review: RT for Extremity Soft Tissue Sarcoma (Haas)

Background

Comprehensive review of radiation therapy for extremity soft tissue sarcoma (STS), synthesizing evidence on RT indications, timing (pre-op vs post-op), dose, technique, and outcomes. Draws on randomized trials (Rosenberg, Yang, O'Sullivan) and major institutional series.

Interventions and follow up

Treatment: Narrative evidence synthesis (review article, not a clinical trial)
Primary endpoint: Evidence synthesis
mFollow up: N/A

Results

Pre-op RT dose: 50 Gy in 25 fractions standard; boost 16 Gy for positive margins
Post-op RT dose: 60-66 Gy in 30-33 fractions
Brachytherapy: Effective for high-grade STS (Pisters MSKCC data); HDR or LDR
IMRT: Emerging evidence for superior conformality and potential local-control benefit

Adverse events

Pre-op RT: Wound complications 35% (O'Sullivan); less late toxicity than post-op
Post-op RT: Fibrosis, edema, joint stiffness
EBRT vs brachytherapy: Comparable toxicity profiles
Bone in field: Pathologic fracture risk 5%

Conclusions

RT is standard of care for most extremity STS treated with limb-sparing surgery. Pre-op RT is increasingly preferred for functional advantages and lower total dose despite higher wound-complication risk. IMRT is increasingly replacing conventional techniques for improved conformality.

Key Limitations

Review article limited to synthesis of existing retrospective and prospective data; no new primary data generated; rapidly evolving field with newer systemic agents and proton therapy not addressed.

Clinical Context

Comprehensive reference for RT principles in extremity STS. Current standard: pre-op RT 50 Gy with surgery within 3-6 weeks, or post-op RT 60-66 Gy starting 4-6 weeks post-surgery. Pre-op vs post-op RT give equivalent local control, with more wound complications pre-op and more late toxicity post-op. High-grade STS >5 cm: RT standard; RT may be omitted for small (<5 cm), low-grade, widely excised, superficial STS.

References