Bridging Gaps in Precision Medicine: Overcoming Patient Leakage and Advancing Personalized Care

Pharmacy Times^® interviewed Edward Kim, MD, MBA, physician-in-chief at City of Hope Orange County and vice physician-in-chief at City of Hope National Medical Center in California, on his presentation at the Precision Medicine World Conference 2025 titled: Overcoming Practice Gaps in Precision Medicine: Addressing Patient Leakage. Kim explained that patient leakage is when individuals disengage from the care process, often due to fear of a cancer diagnosis, language or cultural barriers, logistical frustrations, or miscommunication among care teams. Kim emphasized the need to address these issues by building trust, improving care coordination, and educating patients on their care journey.

Identifying patients who could benefit from precision medicine also poses challenges, particularly due to limited awareness of genetic testing and screening options and the reliance on primary care physicians to drive early detection, according to Kim. The fragmented and non-interoperable nature of electronic health records further complicates efforts to identify high-risk patients, though Kim envisions a future where advanced tools such as AI could help close these gaps.

Pharmacy Times: What are the common reasons patients disengage or "leak" from the care process when referred for precision medicine services?

Artificial intelligence depicts targeted cancer cells in the context of precision medicine. Image Credit: © Wiseman - stock.adobe.com

Edward S. Kim, MD, MBA: I think we need to start with what a definition of disengagement or leakage is. When we talk about patients undergoing this and I can speak more to the cancer world—I'm a medical oncologist at City of Hope, and we are a specialty cancer center. It is a system where you start a care pathway or a care process with a patient, and you're evaluating them. It might be something suspicious, as far as a symptom, or something you find on a radiograph, and then you go down that path of that entire continuum of getting the appropriate testing, the appropriate evaluations, diagnosis with a biopsy, and then eventually treatment, and then survivorship.

Why is it that when you outline something like that, patients will leave? Well, one is that sometimes patients aren't ready to hear—especially in our world—the cancer word. That is a very tough word. Every patient I’ve met and their family members, they still remember the day when they heard that word cancer. It could be cancer. It might be cancer. Those are just as powerful as it is cancer. We know that even for people at risk who undergo genetic testing, hearing that they might have a familial gene or a higher likelihood to develop cancer is also a scary process, so there can be personal reasons why patients leave.

Sometimes it's the level of understanding, not even talking about the way to explain it to a patient on what the process is, how we would approach a precision medicine foundation in trying to evaluate, but sometimes for people it's a language barrier. We have multiple cultures here in Southern California, and so translation doesn't always come across the same way.

Sometimes patients have that trust, and they start the journey, but then get frustrated with the logistics, the lack of coordination that can occur among different teams, as there sometimes are multiple handoffs to different parts of the health care process. So, this can really lead to many reasons—just being frustrated with scheduling and your next test and even sensing there might be some disagreement among the care team can really undermine that trust that the patients really need from a health care provider and a health care team. These are all things we try to really focus on as we not only try to gain the trust of the patient, we try to give them the information to really arm themselves with this information so they can go forward and try to do the best thing for them, so that we can do precision medicine, not just in the screening and the diagnosis and the treatment, but also the survivorship.

This is a long journey. It is one that is constantly changing in our field, but we truly believe it leads to the best outcomes. But these are all very much different parts of this process, and any one of them that breaks down can certainly cause patient leakage to occur.

Pharmacy Times: What challenges do you face in identifying patients who could benefit from precision medicine interventions?

Kim: We do experience challenges in really finding these patients. Of course, the manner in which we always do it is to try and educate, even advertise, even market that we have screening services available, that testing your genetic lineage may be very important, especially if you've had family members with cancer. Frankly, as a medical oncologist, I would love not seeing a patient because we screened them early and were able to diagnose a cancer at its earliest stages that can be cured. So that would make me very happy. I know it would make the patients and their family members very happy as well. So, we continue to try that education, that awareness, so that people come in at the screening level.

Sometimes people don't come in for that screening aspect. Then it's about, what are your risk factors, and this is really on their primary care physicians, way before they would see a specialist. We rely on our primary care physicians, whether they're family physicians, internists, OB/GYN, to really drive home the importance of screening.

We have multiple cancers that you can be screened for. Now, I would hope one day, we would be able to truly integrate our data across electronic medical records. We know this is a big struggle still. If we could do that and then apply some sort of program, I hate to just say AI, because AI is such a huge bucket, but use some sort of smart program that would be able to look inside these data, into these medical records, and identify people who may have risk factors, who have family members with a history of cancer, who have comorbidities that set them up for high risk for cancer, and then making sure that those patients are indeed being screened or in the right places, so that this can occur. I would love that, but right now, it's still a pipe dream in medicine. The types of data we have is a lot, but much of it is unstructured, much of it doesn't talk to each other, and we're going to need to really rethink how we're doing this so that we can holistically identify patients that may benefit from these interventions the most.

I don't have solutions right now. I know the technology exists. I know our databases are out there. It's just, how are we going to put it all together? This really, you feel a lot of empathy when you see patients who could have benefited but didn't because of any one of those institutional barriers, those structural barriers, those data barriers, and certainly awareness barriers.

Pharmacy Times: Are there specific conditions or treatments where you notice gaps present in applying precision medicine practices?

Kim: So, I've spent over 20 plus years—gosh, I sound old—in oncology, and specifically my specialty has been lung cancer and aerodigestive tract cancers. I have to say, what I've seen over the last 20 years occur in lung cancer, in the patients with advanced stage now all the way up to the early stage, even the screening, has been almost a renaissance of how we approach patients. We were finally glad to have screening implemented with low dose CT screening, and those people who were screened are recommended. They're usually above the age of 50 and have a 20 pack-year smoking history. That helps with some folks, but not with those patients or people who develop lung cancer who never had history, had a history of smoking. So, we have a gap there.

We also have a gap because of the population eligible to receive a lung cancer screening test, probably 25% to 30% of them only get the test. So, we need to get that up there, closer to mammogram levels at 90% [or more] and that's hard, because not everybody's aware. Certainly, we rely on our frontline practitioners, like [primary care practitioners], family medicine, etc.

If we look at those patients now who come to us that are diagnosed in advanced disease, so these are people considered incurable, we know the paradigm of treatment has changed so much in that we usually get a bunch of CAT scans or radiographs to establish staging. We need a tissue biopsy to establish a diagnosis, and then there was treatment. That's how we did things in the early 2000s.

Now fast forward, we absolutely have to include genomic testing that is looking at each individual cancer out of each person and identifying different mutations that exist within that cancer and what really drives it into this process. Luckily, we have found 9 or 10 different markers that have unique treatments, and most of these treatments, not all of them, but most of them are pills compared to the intravenous cytotoxic chemotherapy. This has really transformed the field. That patient, if I treated them in the early 2000s, would have a median overall survival of 6 to 9 months. Now with precision medicine, getting the genomic markers, being able to use those markers in the treatment decision making process, and now receiving a pill these people live years. Quite amazing.

So, what's the problem? Well, not everyone is using these markers, even as we continue to report from practices across the country. Actually, there are still gaps in timely collection of these markers and timely utilization to drive treatment decision making, and that can be 60% to 70% in some areas that are using these markers. It should be almost 100%. So, that is a gap that we see.

There are processes that, as we talk about leakage, especially in this precision medicine area, it takes time to get that biopsy, get a diagnosis, making sure you have the amount of tissue that you need to then send it to genomic testing, which can take anywhere between 10 and 14 days, and then it requires the understanding of the physician who ordered it to know what to do with that data. We know there are gaps there. There are surveys done that showed that physicians up to 20% weren't really sure what those markers meant and what they should do. Look, I'm a specialist. I should know what happens in lung cancer, but I feel [like I would be] very challenged if I was a primary care physician or an oncologist in a community based setting where I'm not just focused on one cancer. My first patient maybe has a breast cancer, the second one could have lung cancer, the third one could have colon cancer—that's a lot of different data right there that you got to keep track of, and I think it's very hard to do that.

What other areas does this apply to? As we get more and more smart with molecular testing and different genomics, we're going to see this in rare diseases, which again, becomes very challenging on the front lines. My wife is a psychiatrist, and we hope we see this in mental health areas. Certainly, in cardiovascular disease, where they've used markers in the past to try and identify whether you're having a heart attack or what your risk is, we're going to see this occurring. But especially in lung cancer, where I work, you got to have these different genomic tests done because we know each patient can have a very distinct lung cancer. Even though we call them all adenocarcinoma or non–small cell lung cancer, they can behave very distinctively based on what those genomic characteristics are within that cancer. So, I think it's really our job to really bridge these gaps, close these gaps, so that not only do the patients know that they should be asking for this information, but our physicians have to know where they can get it, and again, leakage can occur if you know that we don't have all these services available.

It is vitally important that we continue this precision medicine course, treating each person as an individual. Their cancers are unique and individual, and knowing that their genomics can be unique, that can tailor to a treatment that could be much more beneficial than our traditional ways of treatment.