APOL1 genotype in African American patients with kidney neoplasm

Context: African Americans (AA) may carry high risk Apolipoprotein L1 ( APOL1) genetic variants that predispose them to significantly higher incidence of chronic kidney disease (CKD) and renal cell carcinoma (RCC). Objective: To study the role of APOL1 risk alleles in patients of African descent with kidney neoplasms. Design: AA patients with nephrectomy procedure for kidney neoplasms were retrospectively studied for APOL1 genotype. Non-AA patients with kidney neoplasm served as control group. Results: Thirty-six AA patients with kidney neoplasms were included. Sixteen (44%) patients carried no APOL1 risk alleles; 13 (36%) patients carried one APOL1 risk allele and 7 (19%) patients carried two APOL1 risk alleles. Increased risk of end stage kidney disease (ESKD) was observed in patients with two APOL1 risk alleles (OR = 3.45). We also observed a higher papillary carcinoma (pRCC) percentage in patients with two risk alleles. Five (71.4%) of the seven patients with two risk-alleles had pRCC. In patients with zero or one APOL1 risk allele ( n = 29), 8 (28%) had pRCC. However, in AA patients with ESKD ( n = 6), only 2 (33%) had PRCC. Among the non-AA patients ( n = 319), 7 (2.2%) patients presented with ESKD, of which 2 (33%) had pRCC. Conclusions: We observed a cluster phenomenon in APOL1 high-risk genotype, ESKD, and kidney neoplasm. We observed significantly more frequent papillary RCC prevalence in AA patients with high-risk APOL1 genotype.