RATIONALE: Sorafenib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor. PURPOSE: This phase II trial is studying how well sorafenib works in treating patients with advanced soft tissue sarcomas.

OBJECTIVES: * Determine the objective response rate (confirmed, complete, and partial) in patients with advanced soft tissue sarcomas treated with sorafenib. * Determine the 4-month progression-free survival rate in patients treated with this drug. * Determine the frequency and severity of adverse events in patients treated with this drug. OTHER OBJECTIVES (if funding permits): * Correlate, preliminarily, a decrease in standard uptake variable (SUV) of target lesions by positron-emission tomography scan at 4 weeks with response in patients treated with this drug. * Correlate, preliminarily, the phosphorylation status of KIT, PDGFR, VEGFR, and the raf/mek/erk pathway with response in patients treated with this drug. * Correlate, preliminarily, the most common B-raf kinase mutation with response in patients treated with this drug. OUTLINE: This is a multicenter study. Patients are stratified according to histology (leiomyosarcoma vs liposarcoma vs angiosarcoma, hemangiosarcoma, or hemangiopericytoma). Patients receive oral sorafenib twice daily on days 1-28. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed every 8 weeks until disease progression and then every 6 months for 2 years and annually for up to 3 years. PROJECTED ACCRUAL: A total of 45-75 patients (15-25 per stratum) will be accrued for this study within 15-38 months.