Phase II Trial of Locally Advanced/Metastatic Soft Tissue Sarcoma or Advanced/Metastatic Malignant GIST

Study Design Type of Study This is an open-label, single arm, prospective, multiple-center phase II study Duration of the Study Period in One Subject Treatment duration is planned for six cycles, unless there is evidence of disease progression or unacceptable toxicity. Patients with continued response after six cycles could receive two additional cycles of therapy. In case complete response and in the absence of unacceptable toxicity, treatment will be continued for at least 2 further cycles to achieve the minimal of 6 total cycles. Study Objectives Primary Objective The primary objective is to determine the response rate of sequential gemcitabine and docetaxel combination in patients with locally advanced/metastatic soft tissue sarcoma or imatinib mesylate refractory GIST. Secondary Objectives The secondary objectives of this study are to determine the time to progression in patients treated with this regimen, the toxicity of this regimen in these patients, the overall survival and the quality of life. Molecular analysis of genetic aberration in soft tissue sarcoma The genetic aberrations of soft tissue sarcoma as reported in literature will be determined. The genetic aberration will be correlated to chemotherapy responses. c-kit and PDGFR gene mutations induced by imatinib mesylate and chemotherapy Those acquired gene mutation of c-kit and PGDFR induced by imatinib mesylate will be first determined. We will also examine further gene mutation of c-kit and PGDFR caused by combination chemotherapy.