Advancements in cancer treatment over the past decade have introduced a growing number of targeted therapies that can inhibit specific genetic mutations driving tumor growth. Despite this progress, many patients are not receiving these innovative drugs, in part because their tumors are not being tested for genetic markers that would identify potential treatment options.
Experts say this gap stems from multiple challenges, including a lack of routine biomarker testing, insufficient tissue samples from biopsies, delays or failures in sending samples for genetic analysis, and doctors not prescribing matched therapies even when mutations are identified. According to specialists, the rapid pace of new drug approvals—averaging about one per week by the U.S. Food and Drug Administration over recent years—has created an overwhelming amount of information for oncologists to track and integrate into clinical practice.
Cost remains a significant barrier. Targeted therapies, often administered orally, can exceed $10,000 per month. While Medicare limits patient out-of-pocket co-payments annually, those without insurance or with private coverage may face financial burdens that can be prohibitive. Physicians and care teams often seek financial assistance programs to help patients afford these treatments, but the process can be time-consuming and unsuccessful for some, limiting access especially in cases of advanced cancer where timely intervention is critical.
Disparities in access are notable, with research showing that economically disadvantaged patients, as well as Black and Hispanic populations, are disproportionately less likely to receive genetic testing and subsequent targeted treatments. This uneven access exacerbates existing inequities in cancer outcomes.
Targeted therapies have been particularly transformative in diseases like lung cancer. Where metastatic lung cancer was once almost uniformly fatal within a short period, dozens of agents now target a range of specific mutations, leading to significantly extended survival times. Some patients with non-small-cell lung cancer who receive early targeted therapy following surgery are even being described by physicians as candidates for cure, a concept once considered unattainable for the disease.
Still, uptake of genetic testing remains suboptimal. One study found that approximately one-third of patients with non-small-cell lung cancer and more than half of those with metastatic breast cancer or colon cancer did not undergo recommended tumor genetic profiling. In colorectal cancer specifically, treatment guidelines advise testing for mutations in five key genes that have implications for therapy selection. Yet only about half of patients receive such testing.
The case of Michael Ebers illustrates these challenges. Diagnosed with metastatic colon cancer, he underwent multiple rounds of chemotherapy, radiation, and surgery, but his care providers initially did not pursue genetic biomarker testing. It was only after seeking a second opinion at Mayo Clinic that his tumor cells were analyzed, revealing a rare mutation present in a small percentage of colon cancers. This mutation is targetable with newer therapies that could halt tumor progression without the severe toxicities often associated with chemotherapy.
Since starting targeted treatment under his new oncologist, Dr. Hao Xie, Ebers has experienced tumor stabilization and improved quality of life. Although not cured, he remains physically active and hopeful, with additional treatment options available should his cancer develop resistance.
A representative from Ebers’s original treatment center stated that genetic testing for colorectal cancer was recommended only at the time of metastatic diagnosis, not at initial or early stages, which may partly explain why testing was delayed.
Medical professionals emphasize that the current disconnect between scientific advances and clinical practice represents a pressing healthcare problem. Increasing the routine use of genetic testing and streamlining the integration of targeted therapies could improve outcomes for many patients, but overcoming financial, educational, and systemic barriers remains essential to realizing the full potential of precision oncology.