Efficacy Comparison Of Pazopanib And Trabectedin Vs Standard Chemotherapy In Second Line Treatment Of Patients With Metastatic Soft Tissue Sarcomas: Experience From Countries With Limited Resources.

e23555 Background: Soft tissue sarcomas (STS) are rare tumors with more than 50 histologic subtypes. Treatment outcomes for patients with STS has improved over the past few decades mostly due to the adoption of a multidisciplinary approach, but still patients with advanced disease have a poor prognosis.Our study compared efficacy of novel sarcoma therapies - pazopanib and trabectedin vs standard chemotherapy, after failure to anthracycline based therapy,in patients with metastatic STS, Methods: In the period between 2014 and 2017 we made a retrospective analysis of 80 patients treated in Clinical Centre University of Sarajevo and University Hospital Centre Zagreb for metastatic STS. All patients received antracycline based therapy as a first line therapy. Patients were grouped in two cohorts. Patients in first cohort received pazopanib and/or trabectedin as a 2nd line treatment. In second cohort patients were treated with standard chemotherapy protocols. Efficacy was assessed in terms of RR(response rate) and PFS(progression free survival). Results: For patients treated with pazopanib PFS in 2nd line therapy was 4.6 months and for trabectidine group 6.15 months. Patients receiving standard chemotherapy as a 2nd line treatment had PFS of 2.0 months. Conclusions: Doxorubicin monotherapy is currently the only standard option for the first-line treatment of STS. For second-line and subsequent lines of treatment, there is no standard therapy. Results of our study confirmed superior efficacy of novel therapies pazopanib and trabectedin over standard chemotherapy. Our results are in correlation with results of pivotal trials (PALETTE and ET743-SAR-3007 trial) for pazopanib and trabectedin. Future clinical trials should adress issues such as sequential therapy, identification of biomarkers and the use of immunotherapy in sarcoma treatment.Clinical studies exploring efficacy of novel drugs in specific histologies are needed.