Feasibility and clinical value of CT-guided 125 I brachytherapy for metastatic soft tissue sarcoma after first-line chemotherapy failure.

Purpose: To evaluate the feasibility and usefulness of computed tomography (CT)-guided iodine ¹²⁵ ( ¹²⁵ I) brachytherapy for patients with metastatic soft tissue sarcoma (STS) after first-line chemotherapy failure.
Methods: We recruited 93 patients with metastatic STS who had received first-line chemotherapy 4-6 times but developed progressive disease, from January 2010 to July 2015; 45 patients who had combined ¹²⁵ I brachytherapy and second-line chemotherapy (Group A), and 48 patients who received second-line CT only (Group B).
Result: In Group A, 49 ¹²⁵ I seed implantation procedures were performed in 45 patients with 116 metastatic lesions; the primary success rate was 91.1% (41/45), without life-threatening complications. Local control rates at 3, 6, 12, 24 and 36 months were 71.1%, 62.2%, 46.7%, 28.9% and 11.1% for Group A, and 72.9%, 54.2%, 18.8%, 6.3% and 0% for Group B. Mean progression-free survival differed significantly (Group A: 7.1±1.3 months; Group B: 3.6 ±1.1 months; P<0.001; Cox proportional hazards regression analysis), but overall survival did not significantly differ (Group A: 16.9 ±5.1 months; Group B: 12.1 ± 4.8 months). Group A showed better symptom relief and quality of life than Group B.
Conclusion: CT-guided ¹²⁵ I brachytherapy is a feasible and valuable treatment for patients with metastatic STS.
Key Points: • ¹²⁵ I brachytherapy is feasible and valuable for treating metastatic soft tissue sarcoma. • ¹²⁵ I brachytherapy represents a prominent activity in disease control. • ¹²⁵ I brachytherapy can achieve better symptom relief and quality of life.