Martin Bradley discusses the potential benefits and barriers to the availability of tumour-agnostic therapies
Significant advances in cancer therapy have been made in recent decades. The elucidation of specific aspects of tumour biochemistry and genetics has led to an increased understanding of the ‘mutational landscape’ of cancer—the various genetic mutations and molecular transformations that drive cancer, and the types of tumour in which these mutations occur.1,2 Targeted cancer treatments that take advantage of this knowledge (as opposed to traditional cytotoxic therapies) have been available for some time. One example is trastuzumab, a monoclonal antibody against the protein Human epidermal growth factor receptor 2 (HER2), which is overexpressed in 20–30% of breast cancer cases owing to overactivity of the HER2 oncogene.1,3 It was later found that some gastric cancers also occur owing to overexpression of HER2, and that trastuzumab was an effective treatment for these cancers, and it was subsequently licensed for this indication.1,3 This showed that targeted treatment can be effective across a range of primary tumours expressing the same genetic mutation. Consequently, research into new oncology treatments has generally focused on these tumour‑specific molecular targets, many of which occur across a variety of histological types. Treatments active against a specific mutation across a variety of primary tumour types are classed as ‘histology‑independent’ or ‘tumour‑agnostic’ therapies.4