Racial and Ethnic Disparities in Preoperative Surgical Wait Time and Renal Cell Carcinoma Tumor Characteristics

Neighborhood social vulnerability and disparities in time to kidney cancer surgical treatment and survival in Arizona

BACKGROUND

Hispanics and American Indians (AI) have high kidney cancer incidence and mortality rates in Arizona. This study assessed: (1) whether racial and ethnic minority patients and patients from neighborhoods with high social vulnerability index (SVI) experience a longer time to surgery after clinical diagnosis, and (2) whether time to surgery, race and ethnicity, and SVI are associated with upstaging to pT3/pT4, disease-free survival (DFS), and overall survival (OS).

METHODS

Arizona Cancer Registry (2009-2018) kidney and renal pelvis cases (n = 4592) were analyzed using logistic regression models to assess longer time to surgery and upstaging. Cox-regression hazard models were used to test DFS and OS.

RESULTS

Hispanic and AI patients with T1 tumors had a longer time to surgery than non-Hispanic White patients (median time of 56, 55, and 45 days, respectively). Living in neighborhoods with high (≥75) overall SVI increased odds of a longer time to surgery for cT1a (OR 1.54, 95% CI: 1.02-2.31) and cT2 (OR 2.32, 95% CI: 1.13-4.73). Race and ethnicity were not associated with time to surgery. Among cT1a patients, a longer time to surgery increased odds of upstaging to pT3/pT4 (OR 1.95, 95% CI: 0.99-3.84). A longer time to surgery was associated with PFS (HR 1.52, 95% CI: 1.17-1.99) and OS (HR 1.63, 95% CI: 1.26-2.11). Among patients with cT2 tumor, living in high SVI neighborhoods was associated with worse OS (HR 1.66, 95% CI: 1.07-2.57).

CONCLUSIONS

High social vulnerability was associated with increased time to surgery and poor survival after surgery.

Diversity in Renal Mass Data Cohorts: Implications for Urology AI Researchers

INTRODUCTION

We examine the heterogeneity and distribution of the cohort populations in two publicly used radiological image cohorts, the Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma (TCIA TCGA KIRC) collection and 2019 MICCAI Kidney Tumor Segmentation Challenge (KiTS19), and deviations in real-world population renal cancer data from the National Cancer Database (NCDB) Participant User Data File (PUF) and tertiary center data. PUF data are used as an anchor for prevalence rate bias assessment. Specific gene expression and, therefore, biology of RCC differ by self-reported race, especially between the African American and Caucasian populations. AI algorithms learn from datasets, but if the dataset misrepresents the population, reinforcing bias may occur. Ignoring these demographic features may lead to inaccurate downstream effects, thereby limiting the translation of these analyses to clinical practice. Consciousness of model training biases is vital to patient care decisions when using models in clinical settings.

METHODS

Data elements evaluated included gender, demographics, reported pathologic grading, and cancer staging. American Urological Association risk levels were used. Poisson regression was performed to estimate the population-based and sample-specific estimation for prevalence rate and corresponding 95% confidence interval. SAS 9.4 was used for data analysis.

RESULTS

Compared to PUF, KiTS19 and TCGA KIRC oversampled Caucasian by 9.5% (95% CI, -3.7 to 22.7%) and 15.1% (95% CI, 1.5 to 28.8%), undersampled African American by -6.7% (95% CI, -10% to -3.3%), and -5.5% (95% CI, -9.3% to -1.8%). Tertiary also undersampled African American by -6.6% (95% CI, -8.7% to -4.6%). The tertiary cohort largely undersampled aggressive cancers by -14.7% (95% CI, -20.9% to -8.4%). No statistically significant difference was found among PUF, TCGA, and KiTS19 in aggressive rate; however, heterogeneities in risk are notable.

CONCLUSION

Heterogeneities between cohorts need to be considered in future AI training and cross-validation for renal masses.

Clear cell renal cell carcinoma molecular variations in non-Hispanic White and Hispanic patients

BACKGROUND

The United States is becoming increasingly diverse, but few molecular studies have assessed the progression of clear cell renal cell carcinoma (ccRCC) in diverse patient populations. This study examined ccRCC molecular variations in non-Hispanic White (NHW) and Hispanic patients and their effect on the association of gene expression with high-grade (Grade 3 or 4) ccRCC and overall mortality.

METHODS

A total of 156 patients were included in VHL sequencing and/or TempO-Seq analysis. DESeq2 was used to identify the genes associated with high-grade ccRCC. Logistic regression analysis was performed to assess whether race and ethnicity was associated with high/moderate impact VHL somatic mutations and the ccA/ccB subtype. Cox regression analysis was performed to assess association of molecular subtype and gene expression with overall mortality.

RESULTS

NHWs had moderate or high impact mutations in the VHL gene at a higher frequency than Hispanics (40.2% vs. 27.4%), while Hispanics had a higher frequency of the ccA subtype than NHWs (61.9% vs. 45.8%). ccA was more common in patients with BMI≥35 (65.2%) than in those with BMI < 25 (45.0%). There were 11 differentially expressed genes between high- and low-grade tumors. The Haptoglobin (HP) gene was most significantly overexpressed in high- compared to low-grade ccRCC in all samples (p-adj = 1.7 × 10^-12 ). When stratified by subtype, the 11 genes were significantly differentially expressed in the ccB subtype, but none of them were significant after adjusting for multiple testing in ccA. Finally, patients with the ccB subtype had a significantly increased risk of overall mortality (HR 4.87; p = 0.01) compared to patients with ccA, and patients with high HP expression and ccB, had a significantly increased risk of mortality compared to those with low HP expression and ccA (HR 6.45, p = 0.04).

CONCLUSION

This study reports ccRCC molecular variations in Hispanic patients who were previously underrepresented.