First-line anthracycline-based chemotherapy for angiosarcoma and other soft tissue sarcoma subtypes: Pooled analysis of eleven European Organisation for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group trials

BACKGROUND: Angiosarcoma is a rare subtype of soft tissue sarcoma (STS). Doxorubicin is the standard first-line chemotherapy for advanced STS. It is not known whether angiosarcoma response to anthracycline-based chemotherapy is different to other STS subtypes. METHODS: Pooled data were analysed from 11 prospective randomised and non-randomised European Organisation for Research and Treatment of Cancer (EORTC) clinical trials of first-line anthracycline-based chemotherapy for advanced STS. Baseline patient characteristics, chemotherapy response, progression free survival (PFS) and overall survival (OS) of angiosarcoma patients were compared with other STS patients. Analysis was performed to identify factors prognostic for angiosarcoma response to chemotherapy, PFS and OS. RESULTS: With a median follow-up of 4.2years, data from 108 locally advanced and metastatic angiosarcoma patients and 2557 patients with other STS histologies were analysed. 25% of angiosarcoma patients had a complete or partial response to chemotherapy compared to 21% for other STS histotypes. The median PFS was 4.9months and OS 9.9months, which were not significantly different from other STS histotypes. In univariate analysis, bone metastases were an adverse prognostic factor for OS (hazard ratio (HR) 1.66, 95% confidence interval (CI) 1.03-2.67; p=0.036). Tumour grade was as an adverse prognostic factor for PFS (HR 1.72, 95% CI 1.01-2.92; p=0.044) and OS (HR 2.03; 95% CI 1.16-3.56; p=0.011). Compared to single agent anthracyclines, doxorubicin+ifosfamide was associated with improved PFS (HR 0.53, 95% CI 0.33-0.86; p=0.010) and OS (HR 0.53, 95% CI 0.32-0.90; p=0.018). CONCLUSIONS: Angiosarcoma response and survival following first-line anthracycline-based chemotherapy was similar to other STS histotypes. Our analysis provides a useful measure of angiosarcoma response to chemotherapy for comparison with future clinical trials