New molecular targets and biological therapies in sarcomas.

The treatment of patients with soft tissue and bone sarcomas has dramatically improved over the last decade. This improvement has been brought about through advances in diagnosis, surgical techniques, conformal radiotherapy, and combination chemotherapy. Further advances in the management of the diverse spectrum of sarcoma patients will reflect tailoring of therapy based on molecular abnormalities. The role of cytogenetics and molecular analysis of fusion or mutated genes in diagnosis, prognosis, and design of biological treatments is discussed. An example of this approach has been the recent success in treatment of patients with gastrointestinal stromal tumours expressing mutant c-kit with a specific tyrosine kinase inhibitor, STI571. Molecular rearrangements may also serve as targets for designing specific immunotherapies with the fusion gene product. The use of biological therapies with signal transduction inhibitors, angiogenesis inhibitors, matrix metalloproteinase inhibitors, immunotherapy, differentiation inducers, and gene therapy could complement existing treatments for long-term control of disease. As these newer biological agents take form, clinical trial design will undergo change to reflect the chronic nature of these therapies.