Discussing Trends in Prostate Cancer - Episode 4
Kristie L. Kahl: What is the difference in the risk for prostate cancer when it comes to African American men compared with Caucasian or Hispanic men?
Dr. Charles Ryan: It’s a very interesting time to think about this question because we're finding out more and more about the relationship of race to prostate cancer outcome. We’ve known for a long time that African American men are more likely to develop prostate cancer compared to Caucasian men. We’ve also known that African American men appear to have a worse prognosis once diagnosed with the disease. That has been something that has permeated a lot of our concern over clinical trials and development over the years. Men from a Hispanic background have an intermediate risk between them and men of an Asian background have a lower risk than Caucasian men. So, while while men in Asia are not free from the risk of prostate cancer it does occur at a lower frequency in the population.
Kristie L. Kahl: Is this risk consistent between newly diagnosed disease and advanced disease?
Dr. Charles Ryan: The conversation about this risk is complicated because it factors in a number of biological and societal factors. The issue around African American race and prostate cancer has long been held that African American men were more likely to initially be diagnosed with advanced prostate cancer, meaning that when they are diagnosed they're more likely to have an aggressive form of it. Now, is this because they were less likely to be screened? Were they not getting the right screening tests? Were the standards of how we looked at normal versus abnormal and needing adjustment, that's been one of the questions. So, that has been an observation now for many decades that African American men are more likely to have advanced disease when they're diagnosed.
What’s changing is that we think there might be some differences in the biology of this disease based on race,and not altogether unfavorable for African Americans. So, for example, there have been some nice analyses that have shown that certain drugs like (Zytiga [abiraterone]), a drug we use quite commonly, is actually quite effective and perhaps even more effective in African American men than in Caucasian men. There’s an immunotherapy called sipuleucel-T, or Provenge, where there have been a couple of analyses that have looked at the outcome of African American men and have shown that it is superior to Aaucasian men when they receive this therapy. Why that is we don't quite know but these are consistent observations that have occurred.
While we talk about the risk of presenting with prostate cancer, is having a disparity where African Americans appear to be at slightly greater risk when it comes to the treatment of advanced disease. That difference might be going away and the other thing that's really interesting and sobering actually is that there have been a number of analyses that have looked at the outcome of African American versus Caucasian men with prostate cancer. They looked at the systems in which the patients are treated. If you look at overall epidemiological data of the country, overall African American men appear to have higher risk, shorter survival, etc. If you look in the VA system, the Veterans Administration system, where basically a veteran walking into the VA hospital in San Diego is probably going to get the same protocol and the same system of care that he would in Boston. These differences lessened so that once you erase differences and treatment patterns, the differences in racial outcomes by race go away. And then if you look at African American men enrolled on clinical trials where we follow very strict protocols in terms of how we treat them and compared to Caucasian men treated on the clinical trials, it actually also shows no real difference in the outcome. That was really a fascinating series of papers to read on that topic because it really said to us that yes while there might be a biological difference, we also need to be mindful of our systems of care and how our systems may fail patients more than the biology might fail them.
Kristie L. Kahl: What factors can we contribute to risk and mortality that's associated with the disease and African American men?
Dr. Charles Ryan: If every patient was matched by a stage with the same treatment, same dose, etc., one might find that African Americans don't have much of a different outcome once diagnosed. When you match them by stage, there might even be certain circumstances where some treatments are preferable for African Americans who have a better outcome. It's really getting the patient diagnosed and it's really the systems that lead to the risks and presenting them to the physician in the first place. That might drive this difference and that's what those papers that I just cited tend to suggest that once you normalize for everything else the outcomes aren't as different as one would think really.
Kristie L. Kahl: Have improved responses to certain treatments contributed to improved survival rates over the years or are there other factors that we can attribute to this increase?
Dr. Charles Ryan: A big factor we can contribute to the increase and improvements in outcome in all patients, including African Americans, would be programs like yours and efforts like yours to get the word out about cancer risk, about treatment, patient involvement and treatment decision making. Yes, the addition of new therapies has had an impact, but I think it's wrapped up in a whole system of improvements that have occurred. We've still got a long way to go. Our system still fails a lot of patients and that's a problem that we need to address in this country.
But we're making headway in terms of understanding our biology of the disease and matching treatments to the biology of the disease. We're making headway in our understanding of who's at risk and who needs treatment. We're also making headway in identifying pockets of the population where we need to go and do screening and identify patients who are at risk whether it be through family history, race disparity of primary care.
Kristie L. Kahl: Are there any ways that African American men can reduce their risk for prostate cancer?
Dr. Charles Ryan: One way to reduce the risk of prostate cancer is to be evaluated early because some people will have pre-cancerous prostate cancer. That could allow them to change to have modified lifestyle. This is a challenging area because there is a lot of very interesting retrospective data on what types of lifestyle activities that one does and lower risk of prostate cancer. So, for example, there's data out there published on the consumption of broccoli, the consumption of salmon, the consumption of coffee and the number of times one vigorously exercises per week. All of those have negative associations with death from prostate cancer, meaning the more you do it the less likely you are to die from prostate cancer. The problem is we don't know if we took a 55-year-old man and who has never eaten broccoli in his life and we had him eat broccoli and salmon every day for five years whether we can alter that risk or whether there's sort of a lifetime of benefits built into some of these lifestyle risk factors. There are studies underway, for example, looking at resistance exercise and dietary modifications prospectively, but the major doubt I have is by the time you get to be 65 years old and you've been in hormonal therapy for your prostate cancer if you haven't really been exercising up until that point, how much is a change in your lifestyle going to be able to do it and how effective is it going to be to?
Kristie L. Kahl: What is your advice to help combat some of these racial disparities in prostate cancer?
Dr. Charles Ryan: It forces us to address some challenges in our system in terms of the delivery of care. It unfortunately, or fortunately, has us confronting some of our systemic biases that we have, that all of us in medicine are thinking about a lot and trying to figure out how we confront some of these intrinsic biases. Whether or not we are failing patients in terms of identifying those through early detection. A health care system that addresses equal care, the issues around primary care and also on all segments of the population could help to combat some of these disparities. I actually think having more African Americans be urologists and oncologists and primary care doctors in addressing this issue is a good thing because we have under-representation of certain urologists and primary care doctors and oncologists. The medical field is making changes in that regard but those changes take generations because people need to be educated and trained and it just doesn't happen overnight. It’s a very complicated situation.
We are making progress and I think some of these observations, where now when we do clinical trials we will analyze the outcomes by race, that helps us to identify disparities. It helps us to identify opportunities for improvements and treatment outcome and it puts the issue really out front and center. One of the great challenges, unfortunately, because of some unfortunate historical events that have happened with regards to research, is to get African Americans on clinical trials. Nobody is questioning why those historical disparities have created this opportunity but we really need to work to get over those challenges so that we can begin to address some of the biological, clinical, societal and economic disparities that are challenging for this field.
Transcription edited for clarity.