Dr. Ben Ho Park explains how genetics is shaping more personalized cancer treatment.
No cancer patient is the same — and no cancer is the same, either. That’s why a one-size-fits-all approach to treating cancer isn’t always the best solution. Precision oncology helps address this by analyzing a person’s cancer down to the tumor’s genetics, including DNA and RNA, to create a more targeted treatment plan. In the future, it may even help determine whether a patient is cured without the need for additional treatments.
Think of DNA as the blueprint for genetic traits and RNA as a copy of DNA that carries instructions for cellular function, including making proteins and regulating gene expression — determining which genes turn on and off.
Breast cancer expert Dr. Ben Ho Park is the director of Vanderbilt-Ingram Cancer Center. Here, he shares insights into the genetic events that lead to cancer — and what that means for the future of treatment.
Question: In a nutshell, what is precision oncology?
Answer: “DNA is the alphabet of our life. Every one of our cells, normal and otherwise, has DNA, with few exceptions. Cancer arises because that DNA mutates and gets altered. The end result is that you have many mistakes in the DNA of cancer cells.
We now have the ability to take a patient’s tumor and understand what those DNA changes are — the ‘alphabet’ that has gone awry — and how they cause that patient’s cancer to grow. Equally important is looking at RNA. Some tests use RNA to identify what we call gene fusions, when one gene is inappropriately joined to another. These fusions can be powerful drivers of cancer growth, and today we have effective medications that target many of them.”
Q: What are the challenges of precision oncology?
A: “If you only look for what you know, you’ll only find what you know. What we’ve been doing with partners is looking beyond that — using what’s called an unbiased whole transcriptome fusion analysis. This approach takes longer, but it allows us to look for all gene fusions, not just the ones we already understand.
We’ve uncovered some remarkable findings. These cases may not be common, but for patients whose treatment is guided by these discoveries, the impact can be significant.”
Q: What is an example of a success story with precision oncology?
A: “A woman was diagnosed with metastatic pancreatic cancer, which is typically very difficult to treat. She has now spent more than three years on a targeted therapy and is doing well.
This was possible because of an unbiased whole transcriptomic RNA fusion analysis — something that would not have been identified through DNA testing alone. Based on those findings, we were able to match her with a therapy targeting that specific genetic change. It’s a remarkable example of what precision oncology can do.”
Q: What advancements in precision oncology are you most excited about?
A: “One area that could redefine precision oncology is what we’re doing for early-stage breast cancer and other solid tumors.
Today, treatment decisions after surgery are based on factors like tumor features, stage and patient age. These decisions are guided by past clinical trials showing that additional therapies, like chemotherapy, can reduce the risk of cancer returning. However, some patients may already be cured by surgery alone.
The question we’ve been working to answer is: Can we develop sensitive blood tests to determine who is cured and who is not?
In the future, precision oncology may look like this: After surgery, a patient has a simple blood draw — a liquid biopsy. If the test shows no remaining cancer, they may be able to avoid chemotherapy. If it detects residual disease, treatment can be tailored accordingly.
Just as importantly, these tests could help us monitor whether treatment is working in real time.
The potential impact is significant. Many patients live with uncertainty about whether their cancer is truly gone. This approach could help remove that uncertainty.”
Q: How might liquid biopsies be used in other ways?
A: “Liquid biopsies may also help detect cancer earlier, even in people without a diagnosis. Researchers are developing highly sensitive tools to identify cancer-related signals in the blood and guide next steps, such as recommending additional screening.
These tests are not intended to replace standard screening methods but to complement them — and potentially reach people who might otherwise miss routine screenings.”
Q: What implications does this have for cancer research?
A: “Precision oncology may also transform how clinical trials are conducted.
Rather than enrolling all patients after surgery — many of whom may already be cured — researchers could focus on those who still have detectable disease. This would lead to smaller, more targeted trials with greater statistical power, helping bring new treatments to patients more quickly and efficiently.”
The Vanderbilt-Ingram Cancer Center is a national leader in patient care and research. Vanderbilt offers the region’s most complete range of oncology care, from advanced imaging to team-based treatment options to genetic cancer medicine and the latest in therapies being studied in clinical trials.
