Supplementary Material for: Outcomes of Systemic Therapy for Patients with Metastatic Angiosarcoma

Background: Angiosarcomas (AS) are rare tumors of vascular origin with a variable behavior and overall poor prognosis. We sought to assess the outcomes of patients treated for metastatic disease. Methods: We performed a retrospective analysis of 119 patients treated for metastatic AS. Outcomes and efficacy measurements of the first and subsequent lines of treatment were analyzed. Results: Median age was 61 years, and the most frequent primary sites were chest wall/breast (31%), viscera (22%) and head/neck (20%). Seventy-three (61%) and 46 (39%) patients received ≥2 and ≥3 lines of therapy, respectively. The most commonly used agents included taxanes and anthracyclines. Median overall survival was 12.1 months. Median times to tumor progression were 3.5 months for first line, 3.7 months for second line and 2.7 months for third line. Among 48 patients evaluable per RECIST, the overall response rate to first line was 30% and <10% in subsequent lines. Doxorubicin, liposomal doxorubicin and taxanes resulted in similar response rates and survival, and there was no apparent benefit for combination chemotherapy. Conclusion: Despite reasonable response rates in the first-line setting, benefit from systemic therapy is short-lived in metastatic AS, and outcomes are poor. Doxorubicin, liposomal doxorubicin and taxanes are reasonable and appropriate choices for monotherapy.