10019 Background: Angiosarcomas (ASs) are rare, aggressive vascular malignancies of endothelial cell differentiation which arise de novo or secondary to radiation therapy (RAS.) A subset of patients(pts) with AS harbor mutations in KDR (VEGFR-2) or overexpression of MYC and/or FLT4(VEGFR-3). MYC & FLT4 gene amplifications occur almost exclusively in RAS. These alterations provide a rationale for investigating agents that target angiogenesis in RAS. In a phase II trial of sorafenib, AS pts had a partial response (PR) of 14%; targeting the appropriate pt population may be essential. We hypothesize that co-amplification of MYC & FLT4 may be predictive of response to sorafenib. Methods: Using our institutional sarcoma database & data query system, we identified AS patients treated with sorafenib at Memorial Sloan-Kettering Cancer Center between 1992-2011. Molecular analysis performed on available tissue. With IRB approval, clinical information was collected. Results: We identified 10 women with RAS that received sorafenib. Average age 68 (range 51-84.) 7 pts had distant metastatic disease. Median lines of systemic therapy prior to sorafenib: 2 (range 1-4.) Sorafenib was first line in 60% of pts, administered at 400mg daily and adjusted for toxicity. Best responses included: complete response (CR) 2/9(22%), PR 1/9(11%), stable disease (SD) 5/9(56%) range 5-23m, progressive disease 1/9(11%) for a clinical benefit rate of (CR+PR+SD) 89%. Responses were seen in patients with lung metastases (n=2) and locally advanced disease (n=1) and were durable for 17, 42 and 26 months. Median duration on therapy was 15 months (range 0-42 months.) 7 pts underwent molecular analysis: co-amplification of MYC & FLT4 3 pts (30%); MYC amplification 4 pts (40%); KDR mutation 0 patients. Of the 3 responders, MYC & FLT4 co-amplification were observed in 2 patients and not evaluated in one. Conclusions: Sorafenib is active against RAS of the breast. In this small series, complete and partial responses were seen in patients with co-amplification of MYC & FLT4. This observation requires further study. Performing molecular studies on all AS pts will help define the pathophysiology of this deadly disease to guide rationale clinical trials.
Growth patterns of lung metastases from sarcoma: prognostic and surgical implications from histology