Epithelioid sarcoma (ES) is a soft-tissue sarcoma (STS) associated with a high local recurrence rate after primary resection and high incidence of distant metastasis. Little is known about clinical course and response to systemic treatments. This retrospective analysis aims to provide a reference for future ES-specific studies.
Data from patients with locally advanced/metastatic ES entered in prospective multi-sarcoma phase II/III trials were pooled: EORTC trial 62012 (doxorubicin vs. doxorubicin/ifosfamide), 62043 (pazopanib), 62072 (pazopanib vs. placebo) and 62091 (doxorubicin vs. trabectedin). Patients had either a local or centrally confirmed diagnosis of ES, inoperable/metastatic disease at study entry and were eligible for the respective trial. Response was assessed using RECIST 1.1. Progression-free survival (PFS) and overall survival (OS) were calculated from date of study entry.
Among 1099 patients with advanced STS, 27 ES patients (2.5%) were eligible (17 male (63%), median age at diagnosis 50 yrs, range 19-72). 18 (66.7%) received chemotherapy as 1st line treatment (5 doxorubicin, 8 doxorubicin/ifosfamide, 2 pazopanib, 3 trabectedin) and 9 (33.3%) received pazopanib in 2nd line or later. Primary tumor was located in lower extremity (N = 8; 29.6%), upper extremity (N = 5; 18.5%), retro/intra-abdominal (N = 4; 14.8%), other locations (N = 10; 37.0%). At study entry, metastases were mainly found in lung (N = 17; 63%), lymph nodes (N = 9; 33.3%), bone (N = 8; 29.6%) and soft tissue (N = 7; 25.9%). Best response for 1st line patients was 4 partial responses (PR, 22.2%), 10 stable disease (SD, 55.6%) and 4 progressive disease (PD, 22.2%). In subsequent lines, pazopanib achieved 1 PR (11.1%), 4 SD (44.4%) and 4 PD (44.4%). All patients but one progressed. Median PFS and OS were 3.8 (95% CI: 2.2-4.8) and 10.8 months (95% CI: 8.1-21.3), respectively. 5 patients were still alive at time of the according trial analysis.
With all limitations of a retrospective analysis of such small dataset, objective response and survival outcomes of this locally advanced/metastatic ES population are relatively poor. The clinical testing of novel agents remains a high priority.
Clinical trial identification
Legal entity responsible for the study
P. Schoffski: Institutional support from Epizyme for advisory functions. T. Brodowicz: Personal fees from Roche (lecture fee), personal lecture and advisory fees from Amgen, Bayer, Novartis, PharmaMar, Eisai and Eli Lilly outside the submitted work. All other authors have declared no conflicts of interest.