Trabectedin Plus Radiotherapy for Advanced Soft-Tissue Sarcoma: Experience in Forty Patients Treated at a Sarcoma Reference Center.

Symptomatic control and tumoral shrinkage is an unmet need in advanced soft-tissue sarcoma (STS) patients beyond first-line. The combination of trabectedin and radiotherapy showed activity in a recently reported clinical trial in this setting. This retrospective series aims to analyze our experience with the same regimen in the real-life setting. We retrospectively reviewed advanced sarcoma patients treated with trabectedin concomitantly with radiotherapy with palliative intent. Growth-modulation index (GMI) was calculated as a surrogate of efficacy. Forty metastatic patients were analyzed. According to RECIST, there was one (2.5%) complete response, 12 (30%) partial responses, 18 (45%) disease stabilizations, and nine (22.5%) progressions. After a median follow-up of 15 months (range 2-38), median progression-free survival (PFS) and overall survival (OS) were 7.5 months (95% CI 2.8-12.2) and 23.5 months (95% CI 1.1-45.8), respectively. Median GMI was 1.42 (range 0.19-23.76), and in 16 (53%) patients, it was >1.33. In patients with GMI >1.33, median OS was significantly longer than in those with GMI 0-1.33 (median OS 52.1 months (95% CI not reached) vs. 8.9 months (95% CI 6.3-11.6), p = 0.028). The combination of trabectedin plus radiotherapy is an active therapeutic option in patients with advanced STS, especially when tumor shrinkage for symptomatic relief is needed.