Molecular oncogenesis of chondrosarcoma: impact for targeted treatment.
The prognosis of patients with unresectable or metastatic chondrosarcoma of the bone is poor. Chondrosarcomas are in general resistant to chemotherapy and radiotherapy. This review discusses recent developments in the characterization of molecular pathways involved in the oncogenesis of chondrosarcoma that should be explored to improve prognosis of patients with advanced chondrosarcoma. The different oncogenic pathways for chondrosarcoma have become better defined. These include alterations in pathways such as isocitrate dehydrogenase mutation, hedgehog signalling, the retinoblastoma protein and p53 pathways, apoptosis and survival mechanisms, and several tyrosine kinases. These specific alterations can be employed for use in clinical interventions in advanced chondrosarcoma. As many different genetic alterations in chondrosarcoma have been identified, it is of the utmost importance to classify druggable targets that may improve the prognosis of chondrosarcoma patients. In recent years an increased number of trials evaluating targeted therapies are being conducted. As chondrosarcoma is an orphan disease consequently all studies are performed with small numbers of patients. The results of clinical studies so far have been largely disappointing. Therapeutic intervention studies of these new targets emerging from preclinical studies are of highest importance to improve prognosis of chondrosarcoma patients with advanced disease.