Novel targeted therapies in the treatment of soft-tissue sarcomas.

Systemic therapy options for sarcomas historically have been limited once these tumors become resistant to traditional cytotoxic chemotherapy. Ongoing preclinical research into their biology and clinical trials based on rational biologic targeting have identified novel therapies. For example, the success of imatinib in gastrointestinal stromal tumor has led to the use of other tyrosine kinase inhibitors in other sarcoma subtypes. Other novel therapies include targeting of the mTOR pathway, and IGF-1 receptor. The heterogeneity of these tumors demands intelligently designed protocols in recognizing efficacy that may be restricted to certain histologic subtypes. This article will cover recent trials of new biologic agents in sarcomas that have exhibited promising activity.