Abstract 76P
Background
Trabectedin, which is approved for advanced soft tissue sarcoma (ASTS) management, has a complex mechanism of action, but can be classified as an alkylating agent. The need to maintain a high relative dose-intensity (RDI) is not clearly established in this clinical setting.
Methods
We conducted a retrospective study in 5 expert centres to compare the progression-free survival (PFS) and overall survival (OS) of ASTS patients according to the RDI calculated over the first 3 cycles (RDI<80% and RDI≥80%). Comparisons of patient’s characteristics were done using Chi-2, Fischer exact and Wilcoxon tests. Associations between PFS/OS and RDI were tested using Log-rank test.
Results
Out of 332 pts treated with T between 09/1999 and 12/2021, 244 have received at least 3 cycles before progression. Among these 244 pts, the median RDI during the first 3 cycles was 83% (range, 48-106%), the mean RDI was 81% (+/- 14.0%) and 106 pts had RDI <80%. An RDI<80% was more frequently observed in pts treated in a centre with a high volume of activity (82/169, 49%, vs. 24/75, 32%, p=0.02), in pts who had previously received pazopanib (12/18, 67%, vs. 94/225, 42%, p=0.04), and in pts who experienced grade 3 neutropenia during the first cycle (56/77, 73% vs. 35/127, 28%, p<0.001). PFS did not significantly differ according to RDI (p=0.08): median PFS=5.9 months (4.4-6.8) when RDI≥80% vs. 8.4 months (7.0-9.3) when RDI<80%. We observed no significant difference in terms of OS (p=0.53): median OS=15.8 months (13.2-19.7) when RDI≥80% vs. 18.2 months (15.6-23.4) when RDI<80%.
Conclusions
This retrospective study does not support a link between high RDI and better PFS or OS for ASTS pts.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Centre Oscar Lambret.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.