Renal Cell Carcinoma in the Canadian Indigenous Population

Abstract

Background: Diagnosis and treatment of renal cell carcinoma (RCC) might be different in Indigenous Canadians than in non-Indigenous Canadians. In this cohort study, we compared RCC presentation and treatments in Indigenous and non-Indigenous Canadians. Methods: Patients registered in the Canadian Kidney Cancer Information System treated at 16 institutions between 2011 and 2018 were included. Baseline patient, tumour, and treatment characteristics were compared between Indigenous and non-Indigenous Canadians. The primary objective was to determine if differences in RCC stage at diagnosis were evident between the groups. The secondary objective was to determine if treatments and outcomes were different between the groups. Results: During the study period, 105 of the 4529 registered patients self-identified as Indigenous. Those patients were significantly younger at the time of clinical diagnosis (57.9 ± 11.3 years vs. 62.0 ± 12.1 years, p = 0.0006) and had a family history prevalence of RCC that was double the prevalence in the non-Indigenous patients (14% vs. 7%, p = 0.004). Clinical stage at diagnosis was similar in the two groups (p = 0.61). The disease was metastatic at presentation in 11 Indigenous Canadians (10%) and in 355 non-Indigenous Canadians (8%). Comorbid conditions that could affect the management of RCC—such as obesity, renal disease, diabetes mellitus, and smoking—were more common in Indigenous Canadians (p < 0.05). Indigenous Canadians experienced a lower rate of active surveillance (p = 0.01). Treatments and median time to treatments were similar in the two groups. Conclusions: Compared with their non-Indigenous counterparts, Indigenous Canadian patients with RCC are diagnosed at an earlier age and at a similar clinical stage. Despite higher baseline comorbid conditions, clinical outcomes are not worse for Indigenous Canadians than for non-Indigenous Canadians.