Dr Cobain on the Importance of Molecular Testing in Metastatic Breast Cancer

Erin Frances Cobain, MD, medical oncologist, co-director, Breast Cancer Clinical Research Team, Rogel Cancer Center, University of Michigan, discusses the importance of molecular testing in patients with metastatic breast cancer.

In considering treatment decisions beyond the frontline setting, molecular testing plays a crucial role in guiding therapy selection for patients in the second- and third-line endocrine therapy settings, Cobain begins. The key takeaway from recent presentations given at an OncLive® Institutional Perspectives in Cancer webinar on breast cancer underscores the critical importance of using molecular profiling wisely to identify therapies that are most likely to yield clinical benefit, according to Cobain. An essential consideration in this context is the timing of molecular testing, particularly in scenarios where patients have experienced extended periods of successful response to first-line treatments, she reports. It is pertinent to reassess tumor molecular features through repeated molecular testing and next-generation sequencing to accurately inform treatment selection based on the current tumor profile, Cobain explains.

When patients exhibit durable responses to initial therapies and require subsequent lines of treatment due to disease progression or resistance, the molecular characteristics within the tumor may have evolved, she continues. A personalized therapeutic approach ensures treatment decisions align with the current molecular landscape of the tumor, optimizing the likelihood of therapeutic efficacy and clinical benefit, Cobain emphasizes.

Moreover, molecular testing beyond the frontline setting serves as a strategic tool to tailor treatment strategies according to the evolving nature of metastatic disease, she expands. Although conducting initial molecular profiling at the time of metastatic diagnosis provides valuable insights, ongoing monitoring through repeated testing offers dynamic information about genomic alterations that may emerge or evolve during treatment, she adds. By integrating real-time molecular data into treatment decision-making processes, oncologists can optimize therapy selection, adapt to changing tumor characteristics, and maximize treatment outcomes for patients with advanced stages of disease, Cobain concludes.