Biomarkers in Molecularly Targeted Therapy for Cancer

Molecularly targeted agents have been successfully introduced into the treatment of patients with cancers. Although, these agents have been shown to improve clinical outcomes for many cancer patients, not all patients benefit from them and a considerable proportion of patients experience severe toxicity that can impair quality of life. To take full advantage of the targeted agents, we need predictive biomarkers of efficacy and toxicity to realize personalized anticancer therapy. However, well-validated biomarkers are currently scarce in targeted therapy, even though the risk of toxicity and high costs cannot be ignored. This article provides a background to biomarkers in molecularly targeted anticancer therapy, and reviews some related patents.