Analysis of clinical factors associated with survival in patients with soft-tissue sarcoma receiving trabectedin

Soft-tissue sarcomas (STSs) are a heterogeneous group of rare malignancies. Treatment for advanced STS usually starts with anthracycline-based therapies, with no clear sequence for further treatment. A preferred option is trabectedin, especially for liposarcoma and leiomyosarcoma (L-sarcoma). However, due to severe side effects and few clinical trials, further research of the parameters affecting survival is necessary for the optimal selection of patients. We retrospectively analyzed 73 consecutive patients with STS treated with trabectedin at the University Hospital Centers at Zagreb and Osijek from 2014 to 2021. Our primary goals were evaluating factors affecting progression-free survival (PFS) and overall survival (OS). The median PFS and OS for trabectedin were 3.6 months and 13.7 months, respectively. Patients with L-sarcoma exhibited longer PFS and a trend towards longer OS compared to those with non-L-sarcoma. However, these effects were primarily a result of the myxoid liposarcoma subtype, which exhibited a median PFS of 21.1 months and a median OS of 33.3 months, both significantly longer compared to non-myxoid L-sarcoma. Additionally, patients with three or more sites of metastases exhibited shorter median PFS (3.1 months vs. 3.6 months) and OS (5.7 months vs. 23.8 months) compared to only one metastatic site. There was no correlation between the PFS values of trabectedin and pazopanib and no difference in survival, regardless of the treatment sequence. Trabectedin treatment yields the greatest survival benefit in patients with myxoid liposarcoma and low metastatic burden, whereas the additional use of pazopanib provides further clinical benefit, regardless of treatment sequence.