RESPOND Study: A Multi-Faceted Exploration into Prostate Cancer's Racial Disparities - Scarlett Lin Gomez

September 15, 2023

Scarlett Lin Gomez discusses the RESPOND study, which aims to understand the disproportionate impact of prostate cancer on African-American men. Dr. Gomez outlines the study's multi-level, socio-ecological approach, which integrates factors from structural racism and healthcare access to tumor biology. Funded by the NCI and the Prostate Cancer Foundation, the study has successfully recruited over 12,000 African-American men from diverse regions, exceeding its initial goal. Dr. Gomez emphasizes the study's unique focus on upstream factors like structural bias in mortgage lending and community engagement through surveys and focus groups. Future steps include exploring the "five A's of access": accessibility, availability, and affordability. The study aims to be a broad resource for clinicians and researchers to improve care for African-American men.

Biographies:

Scarlett Lin Gomez, PhD, MPH, University of California San Francisco, San Francisco, CA

Samuel L. Washington III, MD, MAS, Urologist, Goldberg-Benioff Endowed Professorship in Cancer Biology, University of Southern California, San Francisco, CA


Read the Full Video Transcript

Samuel Washington: Hi everyone. It's Dr. Samuel Washington here with UroToday. Today I'm interviewing Dr. Scarlett Lin Gomez. She is going to talk to us about the RESPOND study and the impact that it's having already in our field. Dr. Gomez is a professor in the Department of Epidemiology and Biostatistics, co-leader of the Cancer Control Program within the UCSF Helen Diller Family Comprehensive Cancer Center, director of the Greater Bay Area Cancer Registry, which is a part of the California Cancer Registry and CR program, as well as project leader for the research on prostate cancer in men of African ancestry, defining the roles of genetics, tumor markers, and social stress study, otherwise known as the RESPOND study. Thank you for taking the time to talk to us about what's going on with RESPOND.

Scarlett Gomez:
Thanks for having me. It's great to be here. So thank you for inviting me to talk a little bit about our study called RESPOND. And I wanted to give a little bit of background on the study, sort of what is motivating us to do this study, and also how we've designed the project, but also some of our very preliminary results. So the is the motivation, the reason why we're really interested and this team of us came together to propose a study called RESPOND is because of this that we have long known that there is a higher burden of prostate cancer among African-American men. This is in fact one of the biggest disparities that we see in the field of prostate cancer, in the field of cancer in general. So specifically this is based on the latest cancer surveillance data. We know that there is a 70% higher incidence rate of prostate cancer among African-American or black men compared to non-Hispanic white men and a more than twofold higher rate of mortality.

There's actually been quite a bit of research done to understand what some of the underlying drivers of these disparities might be. And some of these research have has shown that African-American men tend to be more likely to be diagnosed with more aggressive types and subtypes of prostate cancer. And this is where it gets a little bit controversial. So some studies show that once we adjust for stage of diagnosis, different kinds of treatments that patients receive, as well as indicators of socioeconomic status, like health insurance status, income, and also in studies where there are equal access to care settings, like Veterans Affairs studies and clinical trials, that there may actually be comparable outcomes, including survival, comparing black to white men. But generally, studies that are based on population-based data like NCDB data or CR data, we actually see continuing disparities in survival.


So we think that this is actually a problem that is not yet solved and perhaps we're not quite asking the right questions. We posit that to really think about this from a slightly different standpoint, we really need to consider that there's a continuum of influences on health outcomes and also on health disparities. So this is one ... there's several different kinds of these multilevel socio-ecological models. I really like this one, which was proposed from the Benton Franklin Health District, because it really nicely illustrates the sort of upstream, downstream in terms of the drivers of cancer health disparities. In particular, I want to sort of shift our focus to the upstream factors. So sort of sitting here in the middle are what according to this framework are called the living conditions. These are really the social determinants of health.


We've heard about this term a lot. This is defined by the WHO as the conditions in which people are born, grow, work, live, and age. So these include things like ... these are basically the environments that we live in, the physical aspects of the environment, economic aspects, service aspects, and social aspects of our environments. But these social determinants aren't even the most upstream of what impacts our health. In fact, if we keep moving upstream, we see that the determinants of the social determinants are the structural drivers of health. So the WHO part of the definition refers to the structural drivers as the wider set of forces and systems that shape these conditions of daily life. So these are the extent to which there are inequities on the basis of patients or demographic characteristics in terms of class, race, immigration status, gender identity, sexual orientation, and also intersections of these identities and how our systems are inequitably distributed and service the population on the basis of these inequities.


So how do we parlay this? How do we translate this into research? So our group has been using various multi-level models and approaches for the research that we do. And RESPOND is one major effort in which we're applying these multilevel approaches. So specifically our group proposed this conceptual framework by which upstream factors see such as structural and social determinants lead to disease, aggressiveness, and mortality among African-American men with prostate cancer. So we posit that the very, very upstream structural racism is the major driving factor, the fundamental cause, which in turn leads to social stressors at multiple levels that impact men across their life course. So these levels are at the contextual level as well as at the individual level. These together produce stress over time, which is embodied and has impacts upon tumor biology, immune responses, and different biological systems, but can also impact outcomes through healthcare access, health behaviors, and other pathways as well.


And then these together in turn leads to what we are observing clinically, which is the higher burden of prostate cancer outcomes, both in terms of tumor aggressiveness and mortality. And then at the very bottom we also hypothesize that because there is a strong germline genetic component to prostate cancer, that this pathway may be modified by varying levels of germline risk. So RESPOND, as Dr. Washington mentioned, is a study of prostate cancer among African-American men. It's an integrated set of multiple studies or projects that together is focused on this common theme of identifying the multilevel determinants and characteristics of aggressive prostate cancer. This is funded primarily through the NCI, but we also have funding from the National Institutes on Minority Health and Health Disparities, or NIMHD, and the Prostate Cancer Foundation. So this program, the RESPOND program, is really structured and is for integrative projects.


The overall program leader for RESPOND is Chris Hayman from USC. Myself and my team at UCSF, we lead project one. Chris Hayman leads project two. John Carpten, also from USC, and Franklin Wong here from UCSF, together they lead project three. And Karen Sfanos from Hopkins leads project four. And what are each of these projects? So this is kind of how the projects overlay onto that conceptual framework for RESPOND. Project one, the project on social stressors that we're leading at UCSF, is really kind of trying to measure and tease apart this social stressor, multi-level life course social stressor part of our proposed pathway. Project two, which was led by Chris Hayman, is focusing on the germline risk aspect. Project three, which is led by John Carpten and Franklin Wong is focusing on the tumor biology, specifically tumor genomics. And project four, which is led by Karen Sfanos, is looking at the immune profiles in particular in the tumor microenvironment.


We also have aims that propose to integrate all of these factors together in addition to looking at each of these components separately. So I think that's really one of the novel aspects of RESPOND, really is this right here, the fact that it's very multidisciplinary, coming together up to the table to propose a study that is really closely integrating all of these different perspectives and components together. The other aspect of RESPOND that I think is really noteworthy to point out is that it's a national study. So we are recruiting primarily through cancer registry, so this makes the study what we characterize as population-based. So each of these cancer registries in theory captures all men diagnosed with prostate cancer within their catchment areas.


So the orange dots in this map show you our recruitment sites as well as our collaborative sites. And the cancer registries, the states and the metro regions that we're including, capture almost 50% of all African-American or black men with prostate cancer overall in the US. So this is just one statistic that's coming out of our study. This is one of the measures we're looking at to measure structural racism. This is a measure that our colleague, Kirsten Byer, from the Medical College of Wisconsin developed. It's referred to as the racial bias in mortgage lending measure. So that's really a proxy for a type of redlining. So what she's done is she's taken data from the Home Mortgage Disclosure Act, which is information on every mortgage application. So all banks are required to report this information to this federal for this act. And included in this information, this database of information, is the outcome of each of these mortgage loan applications, as well as some associated characteristics such as the race of the applicant, income level, amount of the loan that they're applying for.


So what this measure is really capturing is the odds of mortgage loan denial in a given neighborhood relative for one group versus another group. So what our measure specifically is looking at is the odds of mortgage loan denial for an African-American applicant versus a non-Hispanic white applicant within a neighborhood. So these are neighborhood-level measures. And what it's really reflecting is the degree of disinvestment or bias in terms of systematic exclusion of certain groups and populations from that particular neighborhood. So what do we see? So if a value is greater than one here, that tells us that that particular neighborhood that the prostate cancer patient is living in is more likely to be denied a home loan compared for to black versus white applicants. And what we saw here was across all the regions in RESPOND that the vast majority of neighborhoods that these men live in, whether you're black or white, have a higher rate of mortgage loan denial for black versus a white applicant.


And in fact, the proportion is stark, and that there are racial differences as well in terms of these neighborhoods, comparing black versus white, where black patients are living in versus white patients are living in. We've done additional analysis associating these measures of structural racism and redlining with outcomes after prostate cancer and are finding that they are significantly associated with outcomes. So that's ongoing. If I have more time in the future, I can share some of those detailed findings or hopefully we'll get them published in the near future. So I just want to end on this. Really, this is kind of the motivation for RESPOND, is that we really need to shift our focus to these upstream factors if our goal is to achieve health equity.


Samuel Washington:
Perfect. Thank you so much for this overview of what's happening with RESPOND. I think it's exciting to understand the scope, magnitude of what's happening, and not just in terms of funds and domains and levels, but also geographically. In terms of the geographic aspect of it, where you are getting information from each of these different centers, what do you hope to gain in terms of insights through RESPOND?

Scarlett Gomez:
I forgot to mention, Sam, that actually our goal initially in this RESPOND study was to recruit 10,000, a cohort of 10,000 African-American or black men fairly recently diagnosed with prostate cancer. As of just a couple of weeks ago, we finished our recruitment and we actually exceeded that goal. So we were able to recruit over 12,000 African-American men from the regions in the map that I showed you. So I think given the geographic scope and coverage, it's really an exceptional opportunity for us. Because of our interest in these geographically embedded factors, that we know that living in Georgia is very different than living in Texas, which is very different than living in California. So I think with the geographic coverage and diversity, we can really start to sort of dig deep at what's going on in these specific areas.

And in fact, if I were to show you a map of that measure of structural bias and racial bias in mortgage lending, it's very different across the regions. And actually, the associations with prostate cancer survival was were very different. So we're really kind of trying to ... because of the breadth of data that we're collecting, it will really sort of allow us to start to disentangle, why is it different? Why does racial bias have a different effect in Georgia than it does in Louisiana, for example? So I think the scope allows us to really dig deep into some of those questions.


Samuel Washington:
I think it's exciting, because some of the measures you're using are very different than what is commonly available to us urologists, for example. So I think it's giving insights to ideas, concepts that say, don't commonly get addressed in my clinic visit. Exciting to kind of understand what happens outside.

Scarlett Gomez:
Yeah, I think increasingly within clinical settings, we are starting to pay more attention to social needs, which I think is really important because it's sort of more proximal, but we also recognize that the extent to which our patients are able to come in for their clinic visits in a timely fashion, make appointments and adhere to the treatments that are prescribed to them has a lot to do with their social needs. But thinking about this conceptual framework, there are further factors that are even more upstream than the social needs. It's the neighborhood environments that impact upon the patient's social needs and it's the policies that are racially biased that are impacting upon the social determinants.

So I think being creative about what measures and what sort of externally available data we can pull in to try to start to get at some of these upstream factors is kind of our goal here. And I think it helps us to ... as providers, as institutions, we can only do so much. So I think our hope is that with these data and as we can start to generate the empirical support for why we do need to start thinking about policies and guidelines if we really want to make an impact on equities.


Samuel Washington:
And I think the natural follow-up to that would be how does RESPOND start to understand what's happening in these neighborhoods, engaging communities and community voices to kind of bridge that data that's coming in?


Scarlett Gomez:
Yeah, I think as with any kind of research in general, it's just so important to engage communities and make sure that the voices of communities are heard. I think in these types of domains and factors that we're studying, that becomes even more apparent, where I didn't talk about it, but within the RESPOND study, our goal really, we administer a survey. So we ask men who participate, who enroll to fill out the survey. And within that survey we ask a lot of questions about what we call social stressors over the life course. So there are things like experiences with discrimination, degree of medical mistrust, but also factors within your neighborhood and stressors that may be occurring or buffers that may be present within your neighborhood. But really to measure those adequately and make sure that our results are really reflecting what's truly going on on in the ground, we need to hear the voices, we need to know what are the life experiences.

When we started RESPOND, we did a series of focus groups at each of our recruitment sites with men with prostate cancer. And we were really heartened to hear collectively from all the sites, all these focus groups, that they were really pleased to see that we were asking these kinds of questions, because they live the stresses from day to day and they see where it's coming from. And I think the idea that stress can impact upon cancer is something that I think is at the top of everyone's mind, but there's just not a lot of research focusing on it. Community has also been really important in RESPOND in terms of this, and has been critical to the success of RESPOND. Each of these sites have really amazing community members that are out there trying to promote the study and trying to just engage with men in the community about the study. And I think without that level of engagement and promotion, we wouldn't have had the successful enrollment numbers that we ultimately did.


Samuel Washington:
Incredibly impressive in terms of overall numbers. In terms of future steps, I guess my specific question would be what do you think this will do to institutions once this data starts to come out? How do you think it may change our paradigms kind of at the center level?

Scarlett Gomez:
That's really a good question. I'd love to engage in further discussions around that. In terms of next steps, we're planning to analyze all of this data that we collected, but we're not going to get to it all because it's so much data. So we're planning the next grant and we want to continue to collect more data, but also continue to do follow-up. And one of the focuses of the follow-up really is on healthcare access, but really trying to dig deep into understanding what are called the five A's of access: accessibility, availability, affordability, and really trying to tease out which aspect is most important in terms of getting the care and communications with their providers as well as surveillance aftercare and quality of life.

So I think in terms of impact upon institutions, hopefully what we're thinking about in terms of the next steps will really help us to get at that, but I really like to think of this as a resource. Yes, we did initially propose this to address some very specific research questions, but our goal really was always that this would be not just the end in itself, but that this would be something that can really be broadly useful and informative. So we definitely invite interested clinicians, other researchers to, if there are questions of interest, how can this ... if there's a particular domain that they think would be relevant to institutions, we would definitely welcome having those conversations about how our study can help to inform those questions.


Samuel Washington:
Perfect. Very exciting. Especially now within urology, there's much more interest, I'd say than 10 years prior, 10 years before that on addressing disparities. So it's exciting to see how this will help all of us across the board who research, study, discuss, treat men dealing with prostate cancer, particularly black men, to improve care. So it's very exciting what's going on. Thank you for taking the time to talk to us. For people who wanted to learn more about the RESPOND study, how would they go about doing it?

Scarlett Gomez:
Well, our website is a great place to start, so that's respondstudy.org, and they can feel free to reach out to any of the investigators on the team as well as myself.

Samuel Washington:
Thank you again for your time. I know you're incredibly busy, but it was great to learn more about RESPOND and what's coming next.

Scarlett Gomez:
Great. Thank you so much for having me, and it's been really great to share.