Before we discuss this article, it's important to emphasize that prostate cancer has the widest racial disparity among U.S. cancer related deaths. Prostate cancer deaths are twofold higher among Black individuals when compared to the average U.S. population, and this disparity has remained stable over the past 40 years despite an overall 50% reduction in prostate cancer deaths following PSA testing. And some of the reasons for this observed prostate cancer mortality rate disparity are, firstly, a higher rate of incident prostate cancer among Black individuals, younger age of cancer onset, and more aggressive prostate cancer at diagnosis among Black men. Also, we know that there's worse survival among Black individuals with local regional cancers, which really amplifies this mortality disparity.
When we talk about PSA testing, we know that PSA testing is associated with a 20% to 30% reduction in prostate cancer deaths at 16 to 25 years of follow-up. This data is from the PLCO and ERSPC screening trials, but it's important to highlight that Black individuals only accounted for about 0% to 3% of the total populations. So needless to say, it is very hard to extrapolate the data from these trials to our Black individuals. But one thing that we can do and has been done before are micro simulation studies, and they've shown that annual PSA testing among Black individuals aged 45 to 69 years is associated with a 35% reduction in prostate cancer deaths. But what these models cannot account for are external factors that are real world factors that may influence prostate cancer screening patterns and behaviors among Black individuals. And so, clearly additional work is needed to better understand how structural determinants of equity, meaning structural racism, laws and policies, economic policies, as well as social determinants of health and healthcare delivery may impact prostate cancer screening among Black individuals.
And so, the study objectives were twofold. First, to examine factors that facilitate to or impede access to PSA testing as experienced with Black individuals, and also to assess the knowledge, the attitudes, and practices regarding PSA testing for prostate cancer screening among primary care physicians and urologists. So this was a mixed method study, and when we say mixed methods, we mean it has both a qualitative and a quantitative aspect. And this was conducted in the Washington, Wyoming, Alaska, Montana, Idaho, and Oregon region. And this study was conducted in partnership with the Black and African-Descent Collaborative for Prostate Cancer Action Group, or the BACPAC, and which is a collaboration of patient, community, advocacy, clinical, and research stakeholders with a national community advisory infrastructure that involves Black individuals as equitable partners in research. And these findings from the study were importantly jointly reviewed with BACPAC advisors to aid in validating the analysis team's interpretation of interview and survey data.
So, we have two populations. We said both the Black individuals, Black men, as well as the primary care physicians and the urologists. So focusing on the first population of Black individuals, these men resided in the Puget Sound region of Washington State. They were recruited by either email or community meetings and events, for example, church-sponsored wellness events. And both the study team and the BACPAC advisors jointly developed interview protocols, recruitment materials, and interview guides to investigate how Black individuals experience structural, social, and interpersonal barriers and facilitators related to prostate cancer screening. These interviews were conducted by an experienced, racially-concordant interviewer who had expertise in cancer related outreach and education in Black communities. With regards to the second population of primary care physicians and urologists, these were from the same region in the northwest, and this study was conducted in partnership with the Washington State Urology Society, the Washington State Medical Association, as well as the WWAMI-O Region Practice and Research Network.
These physicians were given a survey that was focused on attitudes and practices around prostate cancer screening that were adapted for the context of a U.S.-based practice, but using a large national survey of German physicians. And one of the important questions that comes up with these mixed methods studies is, how do we frame the results? How do we interpret them? How do we take these results that are narrated by both the patients and physicians and how do we synthesize them into a mixed method study? And so for the purposes of this study, the study investigators used a prostate cancer disparities theoretical framework and conceptual model. And if we look at the flowchart here, we see that this model up top has four major exposomes or determinants, meaning structural determinants, social environmental, health, as well as biologic. And they start with one and then they incorporate all four together, and then they look at the interaction among these different variables. And then this is fed into a different model that also entails carcinogenesis, screening, as well as symptoms, leading diagnosis, and treatment.
So it really is a complex framework of different aspects that are really integrated to help synthesize these results. And in more detail, essentially what they do is they proceed iteratively, beginning with a set of a priori codes, which are derived from this model and then articulated in the theoretical framework used. And what they do is a construct level saturation that is assessed throughout the analysis until a point which no additional constructs pertaining to the model were identified, which ensures that the sample size was adequate, the patients were adequately... Physicians were adequately interviewed, and they have enough of a result. It's important to note that they collected survey respondent data on both age, sex, race, ethnicity, degree, work experience and setting, and practice type to better understand both the patient and physician populations. And it's important to note that really there are no comparisons being performed here, so there's no quantitative comparative analyses at this point, and they only analyze the results with descriptive statistics.
At this point with this in mind, I'll turn it over to Zach who'll go over the results from this important study. And he'll frame these results in the context of what is available currently in the literature and from the Prostate Cancer Foundation really in order to do a better job in screening and helping our Black men to further reduce this prostate cancer mortality disparity.
Zachary Klaassen: Rashid, thanks so much as always for laying the groundwork for this important study. And so, before we get into the results, let's look at the demographics of the survey respondents. So here we have 31 primary care providers, 32 urologists, 29 patients or interview participants. When we look at race, we see that overwhelming majority of the PCPs, 90%, and urologists, 75%, were White or Caucasian. And in this study, 100% of the patients that were interviewed were Black or African-American. When we look at the PSA or prostate cancer history, we see that 72% of the individuals that were categorized as patients received a PSA test. Roughly half of the patients were diagnosed with prostate cancer. And so, we have a good mix of those that have received PSA screening, as well as those that have been diagnosed with prostate cancer.
I want to also highlight the practice type for these PCPs and urologists. Roughly 55% of PCPs were academic compared to 53% of urologists. And so, we have about one-third of the urologists were private practice in the community, and about 20% of the PCPs were in private practice, 20% in community health centers. So with that background, let's dive into the results. So we're going to have three slides here looking at the survey results. This is part one, looking at access to PSA and availability of information on prostate cancer risk. The first question to highlight is that, are you aware of the 2018 USPSTF Task Force guidelines regarding routine screening? The majority of PCPs were, 80%, as well as urologists, 75%. But where we see a divergence is where the question regarding, do you agree with the 2018 recommendation for prostate cancer screening? And so, we see that only 46% of PCPs completely agree, 40% partially agree, whereas 23% of urologists do not agree, and 67% partially agree.
Let's jump down here to the middle of the table. This is the 2018 AUA guidelines regarding PSA screening. And the question of are you aware of them? Not surprisingly, the majority of urologists were, 87.5%, and only 13% of PCPs were, and 55% had never heard of the AUA guidelines. When we look at the question of, do you agree with the 2018 AUA guideline for prostate cancer screening, 50% of PCPs were unsure, 21.4% did not agree, 21.4% partially agreed. And we see on the urology side, basically everybody either completely agreed or partially agreed. So there's some disconnect here between where information is coming from, whether it be USPSTF for the PCPs, or more commonly for the urologist, the AUA guidelines.
What's interesting is when we look at the next question below that, to what extent do the recommendations from the USPSTF influence your use of PSA screening? Over almost 70% of PCPs strongly or very strongly agreed with the USPSTF, whereas almost 70% of urologists either did not agree or weakly agreed. So again, disconnect with regard to the USPSTF recommendations for prostate cancer screening, which we know are not very aggressive, and we know do not highlight high-risk populations.
So let's move to part two. This is access to PSA testing by physician perception of its value and utility. And the first question is, in general, how important do you think early detection is for reducing death from any cancer? The majority of PCPs and urologists think that early screening is important for reducing mortality from any cancer. But when we look at prostate cancer, we see a difference in results, particularly for the PCPs. Only 13% thought it was very important, 29% important that we should do early screening for detection in reducing mortality from prostate cancer, whereas nearly all of the urologists thought it was very important or important to do early screening to reduce mortality from prostate cancer. When the question was asked, what is your understanding of the value of PSA testing in general, about 50% of PCPs thought that it was valuable, but almost over one third of them were undecided whether that PSA testing was important for patients. Not surprisingly, we see that majority of urologists think that PSA testing is important.
The next question is, do you think PSA testing causes a significant reduction in the chance that a man will die of prostate cancer? Two-thirds of PCPs said no or clearly not, whereas 75% of urologists said that yes, there's a clear proven benefit from PSA screening. The next two questions are important with regards to family history and looking at patients that are Black or African-American. With regards to family history, how often do you discuss PSA testing among those with a strong family history? And it's kind of scattered for PCPs, 30% sometimes, 40% often, 30% always, whereas 78% of urologists said they always talk to a patient with regards to the family history and screening. With African-Americans, again, this is somewhat disturbing in terms of the PCPs, only one-quarter always talk to their African-American patients about PSA testing for prostate cancer, whereas the urologists, 28% often, 59% always. So just in these first two tables of the results, we see some disconnect between what the PCPs think and what the urologists think with regards to not only guidelines, but also PSA testing for high-risk populations.
The third part is looking at assessing access to PSA testing based on mutual trust, and really looking at the dichotomy between the race of the physician or the PCP of the urologist, and the race of the patient. And so, when we look at the cohort from this study, 90% of the PCPs were White, 75% of the urologist, and in terms of not Hispanic or Latinx, 93.5% of PCPs and 93.7% of urologists, and the patients and the participants in this study reported a strong preference for physicians who understand the historical and current-day context of racism, marginalization, and disenfranchisement. And this really lends the fact that there's a push and an appropriate push for increasing not only minorities in medicine, but minorities in urology.
So several limitations from this study. This was a geographical sample that was drawn primarily from the Northwest region of the U.S. There was a higher proportion of interview participants that reported the history of prostate cancer than the overall proportion of Black individuals who will develop prostate cancer in their lifetime, 48% in this study and 17% in the population. Third, the survey sampling approach did not allow calculation of a survey response rate. And finally, Black individuals represent a diverse and heterogeneous population of the U.S. in terms of social and economic status, ethnicities, and cultural norms. And the sample of interviewees in this study may not represent all of these nuances within the overall population. So by way of discussion, the rates of PSA screening certainly have declined among Black individuals following the 2012 USPSTF PSA screening recommendations, and the survey responses highlighted that PCPs rely heavily on these guidelines to inform their practice around PSA testing.
Both patients and physicians come with informed decisions around PSA based screening with substantial knowledge deficits regarding benefits and harms of prostate cancer early detection. We knew this in general, but we certainly see this in this sample of the survey presented today. And finally, PCPs reported low levels of confidence in the value of PSA testing for reducing prostate cancer death. And PCPs also had a lower likelihood than urologists of discussing PSA testing with Black patients and with patients who have a family history of prostate cancer. So we want to highlight a very important guideline that was manufactured by the Prostate Cancer Foundation in 2023. This was the PCF screening guidelines for Black men in the United States. And so this is a snapshot of the six sort of recommendations or statements from the PCF regarding screening. And I want to highlight two important statements that I think really contextualize this study. And so, question four is, at what age should Black men obtain their first PSA test and how often should they be screened for prostate cancer?
In the guidelines... So very clearly recommends that Black men who elect screening, a baseline PSA should be done between the ages of 40 to 45. This is the youngest age we've seen. It's appropriately stated here. And so, I think the guidelines here certainly recommend early screening for Black men regardless of risk. And that leads into question six, how should family history and genetic risk be taken into consideration when screening Black men for prostate cancer? And the statement is, Black men with even higher risk of prostate cancer due to a strong family history and or known carriers of high risk genetic variant should consider initial annual PSA screening as early as age 40. And so, this is really the crux of this whole conversation. This is the information we need to get to the primary care physicians and the urologist in terms of screening men of any risk at 40 to 45, and as early as 40 in men that have a strong family history or may have genetic variants.
So the take home messages from this study are that this study found that Black individuals have unique needs around early detection of prostate cancer. Primary care physicians in this study stated that they do not value PSA testing for prostate cancer early detection, or appreciate its role in reducing the risk of prostate cancer related death. And they were also more likely than urologists to be influenced by guidelines that do not provide specific recommendations for screening high risk populations such as the USPSTF. Finally, incorporating evidence-driven guidance for PSA screening among Black individuals, such as those highlighted in the PCF screening guidelines for Black men into the guidelines that PCPs rely on could improve prostate cancer early detection among this high risk population.
We thank you very much for your attention and for listening to this very important Journal Club discussion. Hope you enjoyed it.