Race Associated With Kidney Cancer Survival Disparities

Author(s):

Across disease stages, Black patients with renal cell carcinoma experience worse survival outcomes than White patients, research has shown.

Limited access to routine medical care may be a factor contributing towards kidney cancer survival, an expert told CURE®

For patients with renal cell carcinoma (RCC; the most common type of kidney cancer), race was associated with survival, with Black patients experiencing worse survival outcomes than White patients, according to findings of a recent study.

In a study of 386,589 patients with RCC, including 46,507 Black patients, findings of which were published in Urologic Oncology: Seminars and Original Investigations, Black patients “were generally younger, had more comorbid conditions, less likely to be insured, in a lower income quartile, had lower rates of high school completion, were more likely to have papillary RCC histology and more likely to be diagnosed at a lower stage of RCC than their white counterparts,” researchers noted.

Survival disparities persisted across disease stages, with Black patients showing 16%, 22.5% and 15% higher risks of mortality than White patients at any stage, with small renal mass or metastatic disease.

“Based on what we found, there are certainly disparities that we've uncovered in survival outcomes among patients who have renal cell carcinoma, which is the most common type of kidney cancer,” said senior author Dr. Nirmish Singla, director of the Kidney Cancer Program at Johns Hopkins Medicine, noting that “socioeconomic disparities between races seem to play a very significant role in influencing survival in renal cell carcinoma as well.”

“And so, I think part of the efforts that we were trying to undertake by looking at these questions would be to essentially try and see if we can disentangle some of the differences in outcomes by race based on either socioeconomic factors, or whether there could be potentially even a biological basis for why there may be differences in the disease outcomes among patients,” Singla said.

Singla was also the senior author on a study, findings of which were presented at the 2023 American Society of Clinical Oncology Meeting and published in the Journal of Clinical Oncology which showed genetic ancestry to be associated with distinct molecular subtypes of clear cell renal cell carcinoma.

Singla spoke with CURE® about his findings and their significance for patients with kidney cancer.

CURE®:What are some of those socioeconomic factors that can affect kidney cancer survival?

Singla: We looked at a variety of factors that were captured by the National Cancer Database or the NCDB, which is a fairly representative national registry that captures about 70% of cancer centers across the United States. Those factors include aspects such as geography, income status, education level, marital status [and] insurance status, among other features as well.

The bottom line conclusion of what we found from our analyses is that, in large part, it seems like access to care — which again, can be multifactorial, whether it is related to insurance status, whether it's related to geographical location in relation to major academic centers or major hospitals, expertise — and routine health maintenance are really important to help with early detection of cancer and for advanced disease, especially in kidney cancer. Access to multidisciplinary care teams, which may include a urologic surgeon, a medical oncologist and in some cases, even potentially a radiation oncologist, may be paramount to optimizing outcomes on an individualized basis.

Not having this access, by not having routine medical care which may be important for the initial diagnosis, but then having access to expertise and multidisciplinary care teams to optimize outcomes when cancer is detected are, the overarching issues that have led to some of the disparate outcomes that might be prevalent from what we covered in our study in the multivariable analysis.

Say there is a patient with kidney cancer who is subject to these disparities and inequities for any number of these socioeconomic factors. What conversations should they be having with their care team to make sure they are receiving the best care possible?

[That is] certainly a loaded question. I think on the one hand, there are certainly many systemic factors, systematic factors, at play in issues that may be hard to address pertaining to access to care. These could range from financially related issues to potentially geographically related issues. A lot of times, a higher level of care tends to sometimes be more centralized, and so even that geographic distance can pose a barrier to seeking the expertise needed to care for certain scenarios.

But I think that as far as actionable things, there are really things that we can do as clinicians on the ground level. I would say that it really starts with education, and certainly, public health awareness, recognizing the importance of forming a trustable healthcare team, whenever it's possible, that can then direct [treatment]. There are evidence-based guidelines out there for managing kidney cancer, certainly, and having access to a team that can follow these guidelines really would be the mainstay of optimizing outcomes and survival among patients.

But there's also maybe a component of cultural barriers to care as well. You know, there are sometimes reasons why patients may be distrustful of our health care system, or at least be suspicious to some extent, and … kidney cancer tends to be diagnosed often incidentally, and patients who are getting routine health care may be those who are more likely to get a scan for one reason or another, and that may lead to an incidental detection of a kidney tumor. But those who maybe are less inclined to having routine care or seeking routine health maintenance may be those that are often diagnosed at a later stage if they're more symptomatic at the time that they pursue the evaluation.

On the genetic side of things, how can these findings regarding racial differences in gene mutations inform treatment plans and treatment strategies between patients and their care teams?

Certainly, if one were to review some of the major kidney cancer trials that have been published and have led to revolutionary treatment for metastatic disease, a closer examination of those trials will actually show that Black patients are disproportionately underrepresented. And so it may be that if there are truly inherent biological or molecular differences in renal cell carcinoma by race, that it may not be really fair to directly extrapolate some of the data from those trials for our approved therapies across all cohorts of patients.

You know, it's very possible that, for example, there may be certain genetic underpinnings for patients who are, let's say, Black, with kidney cancer that is unique to that population that is maybe not as prevalent among [White patients]. Thus, it's very possible that the most optimal treatment could be something that's directed accordingly, like a targeted type of treatment or some combination regimen that may be more ideal for certain populations based on underlying genetics.

So, there could be an argument that maybe the underlying biology in the pathogenesis of kidney cancer itself can be very different based on the types of molecular findings that essentially drive the development of these cancers. But that's something that I think there's certainly more work to be done in that area. That's part of that question of disentangling: What are the systematic issues and socioeconomic issues at play that account for some of those differences that we see in survival versus what are actually truly biological differences that may impact response to treatment?

Transcript has been edited for clarity and conciseness.

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