Precision medicine is no longer a future ambition in oncology — it is now central to how targeted therapies are developed and delivered. For Robert Getzenberg, US Medical Head Gastric Cancer at Astellas Pharma, diagnostics play a critical role in ensuring that patients receive the therapies most appropriate for their disease.
In gastric and gastroesophageal cancers, biomarker testing is especially important because targeted treatments depend on identifying the right patients. A therapy can only reach its full potential if clinicians have access to reliable tests that show whether a patient is likely to benefit.
Getzenberg emphasizes that a clinically useful biomarker must go beyond scientific interest. It needs to be accurate, validated and practical in real-world care. Sensitivity and specificity matter, but so does whether the test can be adopted broadly across laboratories, geographies and clinical settings. A strong diagnostic strategy must therefore consider not only the biology of the marker, but also the platform, workflow, pathology requirements and global scalability.
One example is Claudin 18.2, a biomarker introduced into gastric and esophageal cancer care. Bringing a new test into practice required more than developing the assay itself. It also required early engagement with oncologists, pathologists and testing laboratories so that the clinical community understood how to use the test, how to validate it and how to incorporate it into existing workflows.
This highlights a broader challenge in companion diagnostics: even the best biomarker has limited value if it cannot be accessed by patients. Education, laboratory readiness, tissue management and coordination between oncology and pathology are all essential to successful clinical adoption.
Looking ahead, oncology diagnostics are expected to have impact across the full cancer care pathway. Earlier detection remains a major goal, particularly in cancers such as gastric and pancreatic cancer that often present late. Diagnostics will also continue to shape patient selection, treatment monitoring and understanding of resistance.
Newer approaches, including next-generation sequencing, immunohistochemistry and blood-based testing for circulating tumor DNA, RNA and tumor cells, may help clinicians define disease more precisely and detect treatment response earlier than imaging alone.
As targeted oncology continues to evolve, biomarker testing will become even more important. The future of cancer care will depend not only on developing innovative therapies, but also on ensuring that diagnostics are practical, accessible and integrated into everyday clinical decision-making.
