Compatibility Check: Can Precision Medicine and Pathways Co-Exist?

For many years, the oncology industry has progressed toward standardized care using evidence-based pathways as a method of improving outcomes and reducing the cost of cancer care. Now, one of the most widely talked about trends in healthcare is precision medicine, which uses detailed genetic information about a patient’s cancer to more precisely treat the disease, effectively targeting the tumor. This heightened awareness raises an important question: are precision medicine and pathways compatible?

On the surface, precision medicine and pathways seem to conflict with each other. After all, it seems counterintuitive for physicians to “personalize” care based on a patient’s genetic make-up, yet also follow standardized treatment guidelines set forth by evidence-based pathways. A closer look at the goals and methods of both, however, reveals that not only are precision medicine and pathways compatible, but they are also similar and most certainly complementary, in some ways.

As a result of ongoing research and drug development, the number of drugs available for treating cancer has significantly increased. Variation in treatment patterns can vary widely, and accumulated evidence suggests that some treatment options are more effective and/or less toxic than others. Both precision medicine and pathways help identify appropriate diagnostic testing, procedures, and effective treatment options. Pathways, developed and adopted by oncologists, use broad-based guidelines as a foundation to narrow treatment recommendations. They originated as a means of standardizing care, with the primary goal of improving the quality of care patients receive, and are designed to limit variation without compromising clinical efficacy. The goal of pathways is to match the right patient with the right treatment. Sounds familiar, right? When you look at precision medicine, the goal is very similar. By understanding more specifically a tumor’s biology, drug developers can focus on treatment that specifically targets the mutation causing the tumor or the tumor’s growth. Precision medicine is not a new concept. It has been around for quite some time and has already proven that increasing understanding and knowledge of human genomes and their effect on cancer and other diseases has a profound effect on how we assess risk and make treatment decisions. Perhaps the most well known example is the identification of HER2/neu protein expression. This important discovery in the mid-1980s dramatically changed the way we identify women with elevated risk due to HER2 protein overexpression, as well as how we treat women with HER2-positive breast cancer.

Another example is the EGFR mutation, which may be present in a subset of patients with non-small cell lung cancer (NSCLC). In 2011, ASCO issued a provisional clinical opinion on using EGFR testing to help predict the benefit of treating patients with advanced NSCLC with an EGFR-targeted tyrosine kinase inhibitor (TKI). This recommendation occurred because data were reported that indicated that lung cancer patients with an EGFR mutation are more likely to respond to targeted therapy compared with patients without the mutation. Pinpointing this mutation in patients who have NSCLC helps direct oncologists to the most effective treatment option. The recommended first-line treatment for patients with NSCLC with the mutation is an EGFR TKI instead of the conventional approach of combination chemotherapy for patients without the EGFR mutation.

These examples highlight an important link between precision medicine and pathways. In both cases, identification of genetic mutations is key to offering treatments most likely to have a beneficial effect on a patient’s disease. In addition, pathways, developed by reviewing research, best practices, and expected outcomes, point physicians to the lines of treatment proven to impact the quality of patient care and lead to improved outcomes.

Since President Obama’s announcement of the Precision Medicine Initiative earlier this year, precision medicine has received a great deal of attention. There has been much discussion about the role it will play in how physicians diagnose and treat patients in the future. Most experts agree that it will have a major impact on the future of healthcare as physicians are able to more specifically target treatment to a patient’s disease.

The hope is that the investment in precision medicine by the National Institutes of Health will deliver on its promise to speed the rate of advancing knowledge about many diseases. As it does, it will also create the need for doctors to discern which patients should be tested for which mutations and when. As with most new diagnostics testing, technologies, and treatments, genetic testing costs can be significant and are not necessary or recommended for every patient. Not only will pathways continue to be relevant as a means to reduce variance in care and thereby improve outcomes, but they will also be important tools for providing guidelines to physicians on how and when to employ testing.

Jody Sheehan Garey, PharmD, is senior manager of clinical content & pharmacy services for McKesson Specialty Health and The US Oncology Network.