Racial disparities in renal cell carcinoma histology and outcomes: Insights from the French Kidney Cancer Research Network (UroCCR-191).
Authors: Lu Xiaofan , Bernhard Jean-Christophe , Audenet Francois , Doumerc Nicolas , Merlin Pierre , Roupret Morgan , Waeckel Thibaut , Champy Cécile , Surlemont Louis , Olivier Jonathan , Branger Nicolas , Parier Bastien , Gaillard Victor , Bruyere Franck , Fontenil Alexis , Michel Constance , Vignot Louis , Descotes Jean Luc , Bigot Pierre , Malouf Gabriel G. 
Published: February 2025

442

Background:
In the U.S., racial disparities in renal cell carcinoma (RCC) are documented for common histologies, highlighting differences in incidence and outcomes between Black and non-Black patients. Such disparities are underexplored in European populations, especially across a broader histology spectrum within a universal healthcare system. We aim to investigate racial disparities in RCC histologies and their outcomes among Black and non-Black patients in France.
Methods:
We conducted a retrospective cohort study utilizing the UroCCR database, spanning from March 1957 to May 2024. This multicenter study, referred as UroCCR-191, involved 30 tertiary centers in France, analyzing 9,404 patients (338 Black and 9,066 non-Black) with confirmed histology. Patients with unknown racial background or unidentified/multiple histologies were excluded. Histological distribution, demographics, clinical presentations, tumor features, and outcomes were compared.
Results:
Clear cell RCC (ccRCC) was more prevalent among non-Black patients (68.8% vs 47.6%; odds ratio [OR]: 2.4,
p
< 0.001). Non-clear cell histologies were more common in Black patients, including papillary RCC (23.1% vs 11.8%,
p
< 0.001), the rare clear cell papillary renal cell tumor (1.5% vs 0.5%,
p
= 0.044), and other rare molecularly-defined histologies such as translocation RCC (2.1% vs 0.6%,
p
= 0.005), FH-deficient RCC (0.6% vs 0.1%,
p
= 0.067) and renal medullary carcinoma (0.3% vs 0,
p
= 0.001); all with OR ≥2 and a false discovery rate <0.15. Black patients were younger at diagnosis, with earlier-stage tumors and higher rates of partial nephrectomy. No significant differences were observed in cancer-specific survival; however, Black patients showed better distant recurrence-free survival (hazard ratio [HR]: 0.55,
p
= 0.020). Race was not an independent prognostic factor when accounting for other clinical variables (Table).
Conclusions:
Black patients in France exhibit higher incidences of non-clear cell RCC and are diagnosed at earlier stages compared to non-Black patients. The absence of race as an independent prognostic factor, unlike U.S. data, highlights the potential influence of healthcare systems in modulating racial disparities. This underscores the need for tailored RCC management that considers racial backgrounds to refine diagnosis and outcomes.

Hazard ratios using multivariate Cox regression for predictors of distant recurrence-free survival.

Variable
Reference group
Comparison group
HR
95% CI

p
-value

Race
non-Black
Black
0.96
0.51-1.79
0.889

Age (years)
≤63
>63
1.25
1.07-1.47
0.005

Sex
Female
Male
1.29
1.09-1.53
0.004

Nephrectomy type
Partial
Radical
2.98
2.46-3.61
<0.001

T stage
T1 + T2
T3 + T4
2.36
1.96-2.85
<0.001

N stage
N0
N1 + N2
2.84
2.25-3.58
<0.001

Fuhrman grade
1 + 2
3 + 4
2.39
1.97-2.91
<0.001

Histology
ccRCC
non-ccRCC
0.81
0.65-1.01
0.062