6.O.01 POTENTIAL CHEMOTHERAPY APPROACHES FOR ADVANCED ADULT TYPE SOFT TISSUE SARCOMA

Abstract

Soft tissue sarcomas (STS) include a spectrum of his-tologically and clinically different tumors. Patients are typically relatively young and the course of disease is characterized by early metastasis as well as limited response to chemotherapy. However, a few subtypes such as small round cell tumors (SRCTs) and rhabdomyosarcoma (except from pleomorphic), are considered chemotherapy-sensitive. In addition, reflecting successful translational research of recent years, gastrointestinal stromal tumor (GIST) and dermatofibrosarcoma protuberans have become model diseases for targeted oncological therapy. With a very limited number of active compounds at hand, treatment choices in metastatic STS with inkonsistent genomic alterations were easy to overview until only a few years ago. However, with novel therapeutic strategies such as the antiangiogenic approach and a multitude of novel compounds available both outside and within clinical studies, it may have become more difficult to keep track of currently available treatment options and their clinical safety and efficacy. Anthracyclines with or without ifosfamide are still considered standard of care in most STS-subtypes, especially in high-grade tumors. There is no evidence-based recommendation as to second-line treatment options. However, a number of established compounds, including dacarbazine/temozolomide, gemcitabine, taxanes, trofosfamide, DNA topoisomerase I inhibitors, DNA minor groove binders, and bendamustine, have shown activity. Recently, trabectedin, a DNA minor groove binder initially isolated from a sea sponge, has proven effective and received European approval for use in treatment-refractory STS. In addition, novel compounds such as bevacizumab, multityrosine kinase inhibitors, mTOR inhibitors, imatinib mesylate, and the thrombospondin agonist ABT 510 represent attractive partners for the above-mentioned cytostatic agents or may even be effective single agents in the clinically advanced setting. Novel combinations are being evaluated in clinical studies. In order to be successful, we may have to combine not only different compounds but also different targets beyond the proliferation machinery of sarcoma cells such as tumor angiogenesis, the tumor stromal compartment or tumor cell oncogene products.