Once the impact of COVID-19 begins to minimize and activities settle into a “new normal,” efforts to expand precision medicine across many diseases will resume.
In the simplest terms, precision medicine is the “right test for the right patient at the right time.” But the practice of precision medicine is not so simple. A physician must choose from an array of complicated tests that are appropriate for a diagnosis and the creation of a treatment plan for their patient in a timely manner. That’s a lot of separate data and time points to manage for one patient, so how do we connect these individual patients together with their own personalized sets of tests and outcomes to improve population health?
We can look to breast cancer, where precision medicine has played out for the past decade and has paved the way for standard biomarker testing guidelines, risk assessment and screening protocols, as well as treatment plans that are now widely recognized and used. This clinical application of precision medicine has resulted in the avoidance of unnecessary and ineffective testing and treatment, rapid identification of targeted treatments with good responses in similar populations, and the proactive screening of families at high risk for breast cancers.
Hormone receptor and HER2 testing has become routine for primary invasive carcinomas, and recurrent and metastatic breast tumors. Knowing the estrogen receptor, progesterone receptor, and HER2 test results within a few days of a biopsy allows an oncologist to determine if a patient might benefit from hormone or anti-HER2 therapy. For patients who did not have a hormone receptor or HER2-positive test result or who did not respond to a standard “one size fits all” treatment plan, comprehensive tumor profiling can provide a personalized set of targeted therapy options that are uniquely matched to the tumor mutations. Additionally, women with early stage, lymph node–negative breast cancer can undergo a 21-gene profiling test to determine if they need chemotherapy, once again getting the right treatment for the patient.
Approximately 5% to 10% of breast cancers can be attributed to an increased risk from inheriting a pathogenic gene mutation in BRCA1 or BRCA2. Genetic counselors choose an appropriate test for each family member of the affected, and then follow-up with regular monitoring plans for those with inherited pathogenic mutations. Catching a disease early requires the right test at the right time, which is why large-scale population screening, such as BRCA testing, is recommended at earlier ages for high-risk families and populations.
The big picture comes together in precision medicine when clinical outcomes are linked to the biomarker testing choices, disease screening methods, and targeted treatment plans for large groups of patients as part of clinical trials and translational research. With the analysis of “big data” comes new and updated biomarker testing recommendations, patient care models, disease screening protocols, and treatment guidelines by professional medical societies. These guidelines reflect the most recent technological advances in laboratory science from the bench to the bedside, and this information is continually evolving with new studies leading to better survival rates, increased detection, and improved treatments for future patients.
Like all aspects of healthcare, the emergence of coronavirus disease 2019 (COVID-19) has impacted many different areas of precision medicine. The pandemic has certainly hindered surgeries, and therefore, testing on biopsy tissue. Consequently, oncologists are expecting a wave of more advanced cancers at diagnosis due to delayed biopsies and other issues, such as postponed preventative screening and medical appointments that were put off because patients with suspicious symptoms were afraid to see physicians during the COVID crisis. Providers have tried to ensure the safest environment possible for patients by adjusting how they operate. For instance, some commercial laboratory vendors that offer liquid biopsy testing have implemented mobile phlebotomy to do the necessary blood draw at the patient’s house rather than in the clinic, but tissue is still needed for the initial diagnosis. Undoubtedly, there will be ramifications from these delays, as the earlier cancer is detected, the better the outcome.
Once the impact of COVID-19 begins to minimize and activities settle into a “new normal,” efforts to expand precision medicine across many diseases will resume. As more physicians learn the lessons of how breast cancer incorporated biomarker testing, disease screening, and targeted therapies into standard practices, support for this promising approach to personalized care will continue to grow for the betterment of individuals, families, and populations.
Jen Buhay, PhD, is the precision medicine clinical program manager for The US Oncology Network, leading biomarker testing, education, and operational efforts to support personalized patient care for oncology. Previously, she led precision medicine initiatives in a community hospital setting and worked as a laboratory scientist for commercial and academic molecular diagnostic laboratories. Dr Buhay holds a PhD in Integrative Biology (molecular genetics and computational biology) from Brigham Young University, an MS in Biology from Eastern Kentucky University, and a BS in Animal Behavior from Juniata College. She is board-certified as a molecular biologist through the American Society for Clinical Pathology.