Until now treatment for most types of cancers have been chosen according to the size of the tumour, metastasis as well as morphology of the tumour observed under a microscope. These kind of classification remains important. Nevertheless, the discovery of molecular drivers of cancer and the development of technology to identify biomarkers in tissues have introduced new step of classification for some cancers – one based on molecular subtypes.

However, biomarkers alone do not complete the puzzle. Often, the answer to a genetic testing result is targeted therapy. The identification of biomarkers and the discovery of targeted therapies have led to recent advances in cancer treatment.