Metastatic cancers have historically been identified by their organ of origin, and treatment decisions are made on the basis of this classification. However, with the recent emergence of precision oncology research and molecular profiling, a growing disconnect suggests that the old tumor naming method needs to change. It has been shown that some mutations occur across multiple tumor types and that most tumor types can be subdivided into different molecular subgroups. For example, lung cancers can have mutations in the epidermal growth factor receptor gene, mesenchymal epithelial transition gene, or anaplastic lymphoma kinase gene.
Fabrice André, MD, PhD, and colleagues recently published several arguments as to why tumor naming needs to change considering current research trends. First, classifying tumors by organ of origin stalls progress and has led to delays in treatment for millions of people. The authors cited the delays in research of programmed cell death protein 1 inhibitors caused by the need to conduct clinical trials sequentially for each disease type. This resulted in millions of people with tumors expressing high levels of programmed death-ligand 1 unable to receive relevant drugs because trials had not yet been conducted for their type of cancer. More specifically, patients with certain breast or gynecologic cancers had to wait 7 to 10 years to access these therapies. Similar effects have impacted patients’ access to poly(ADP-ribose) polymerase inhibitors.
Classifying cancer by organ of origin also hinders medical education and patient understanding. Knowledge of molecular mechanisms would make it easier for students to remember the outcomes of clinical trials and potentially improve patient adherence to treatment. Each patient is affected by around 1 to 4 molecular alterations, so molecular-based classification would limit the amount of new information any one person would need to receive and may help guide treatment decisions and adherence.
Molecular-based classifications are likely to become ever more important as further advanced biotechnologies are developed and approved. Regulatory agencies are beginning to shift to approving drugs that focus on a molecular target rather than the organ of origin, but a much greater shift is needed across all regulators and the cancer community at large to achieve a change. Several things will need to be done differently, starting with improved guidance as to whether a specific molecular alteration should be prioritized over the organ of origin. Some societies and regulatory agencies, such as the European Society for Medical Oncology and the US Food and Drug Administration, have begun to develop such guidelines. Widespread acceptance and implementation, access to molecular testing for patients, and medical student education will be other critical steps.
High level
To best utilize the vast body of research in precision oncology, tumor naming needs to change across the cancer community worldwide. Shifting to molecular-based classification of cancers will require radical changes in how medical oncology is structured, conducted, and taught. Regulatory bodies have a key role in supporting this shift, through guidance and approvals. Academic hospitals and cancer centers with expertise in molecular oncology can help support this effort by establishing organ-agnostic teams centered around interpretation of molecular analyses. Fellowships could help transfer knowledge between institutions and raise awareness of the benefits of prioritizing molecular mechanisms when determining treatment plans.
Ground level
As the regulatory agencies and insurance companies begin to recognize that tumor naming needs to change, clinicians should shift their approach to diagnosis and treatment plans. Some cancer centers are developing ways to perform molecular analyses themselves to give more patients access to these diagnostic tests. Additionally, artificial intelligence is being used to identify genomic abnormalities from routine pathology slides at low cost.
