Breaking Barriers: Addressing Issues of Inequality in Trial Enrollment and Clinical Outcomes for Patients With Kidney and Bladder Cancer

Comparative Genomic Landscape of Urothelial Carcinoma of the Bladder Among Patients of East and South Asian Genomic Ancestry

BACKGROUND

Despite the low rate of urothelial carcinoma of the bladder (UCB) in patients of South Asian (SAS) and East Asian (EAS) descent, they make up a significant portion of the cases worldwide. Nevertheless, these patients are largely under-represented in clinical trials. We queried whether UCB arising in patients with SAS and EAS ancestry would have unique genomic features compared to the global cohort.

METHODS

Formalin-fixed, paraffin-embedded tissue was obtained for 8728 patients with advanced UCB. DNA was extracted and comprehensive genomic profiling was performed. Ancestry was classified using a proprietary calculation algorithm. Genomic alterations (GAs) were determined using a 324-gene hybrid-capture-based method which also calculates tumor mutational burden (TMB) and determines microsatellite status (MSI).

RESULTS

Of the cohort, 7447 (85.3%) were EUR, 541 (6.2%) were AFR, 461 (5.3%) were of AMR, 74 (0.85%) were SAS, and 205 (2.3%) were EAS. When compared with EUR, TERT GAs were less frequent in SAS (58.1% vs. 73.6%; P = .06). When compared with non-SAS, SAS had less frequent GAs in FGFR3 (9.5% vs. 18.5%, P = .25). TERT promoter mutations were significantly less frequent in EAS compared to non-EAS (54.1% vs. 72.9%; P < .001). When compared with the non-EAS, PIK3CA alterations were significantly less common in EAS (12.7% vs. 22.1%, P = .005). The mean TMB was significantly lower in EAS vs. non-EAS (8.53 vs. 10.02; P = .05).

CONCLUSIONS

The results from this comprehensive genomic analysis of UCB provide important insight into the possible differences in the genomic landscape in a population level. These hypothesis-generating findings require external validation and should support the inclusion of more diverse patient populations in clinical trials.

Factors associated with clinical trial participation for patients with renal cell carcinoma

OBJECTIVE

Recruitment of a diverse and representative study population is critical to the external validity of oncology clinical trials. The primary objective of this study was to characterize the factors associated with clinical trial participation for patients with renal cell carcinoma and the secondary objective was to examine differences in survival outcomes.

MATERIALS AND METHODS

We used a matched case-control design by querying the National Cancer Database for patients with renal cell carcinoma who were coded as having enrolled in a clinical trial. Trial patients were matched in a 1:5 ratio to the control cohort based on clinical stage and then sociodemographic variables were compared between the 2 groups. Multivariable conditional logistic regression models evaluated factors associated with clinical trial participation. The trial patient cohort was then matched again in a 1:10 ratio based on age, clinical stage, and comorbidities. Log-rank test was used to compare overall survival (OS) between these groups.

RESULTS

From 2004 to 2014, 681 patients enrolled in clinical trials were identified. Clinical trial patients were significantly younger and had a lower Charlson-Deyo comorbidity score. On multivariate analysis, male patients and white patients were more likely to participate compared to their Black counterparts. Having Medicaid or Medicare negatively associated with trial participation. Median OS was greater among clinical trial participants.

CONCLUSION

Patient sociodemographic factors remain significantly associated with clinical trial participation and trial participants experienced superior OS to their matched counterparts.

Geography Should Not Be an "Oncologic Destiny" for Urothelial Cancer: Improving Access to Care by Removing Local, Regional, and International Barriers

Urothelial cancer care is particularly susceptible to geographical health disparity given its complex nature, requiring access to several specialists such as a urologist, a medical oncologist, a radiation oncologist, a surgical oncologist, and multidisciplinary care teams. Furthermore, other barriers to care access in underserved areas include travel burden, longer wait times, late-stage disease at the time of diagnosis, cost, type of treatment, less enrollment in clinical trials, lack of follow-up among cancer survivors, and less research funding in this area. Here, we discuss the impact of geographical location on access to urothelial cancer care, management decisions, and outcomes and we reflect on how to address geographical disparities in care delivery.