Targeted therapies in cancer

Cytotoxic chemotherapy has traditionally provided the backbone of medical care for cancer. While chemotherapy remains the treatment of choice for many types of cancer, so called ‘targeted therapies’ are now increasingly available within the clinic across a broad range of tumour types. Targeted therapies can inhibit specific molecular targets implicated in cancer or single oncogenic drivers, preventing cell growth and tumorigenesis. While often better tolerated, they can be associated with adverse events that require specialist multidisciplinary management. Targeted therapies have changed cancer care, tailoring treatment to an individual patient's tumour characteristics and improving outcome. However, associated with this has come an increasing burden on health economics. Rather than a disease-specific approach, targeted therapies may be of benefit in multiple cancer types. There are three main categories of targeted therapies: small molecule inhibitors, monoclonal antibodies and immunotherapies, which will be considered in this article.