Racial/ethnic differences in cancer risk after kidney transplantation

Transplant recipients have elevated cancer risk, but it is unknown if cancer risk differs across race and ethnicity as in the general population. US kidney recipients (N = 87,895) in the Transplant Cancer Match Study between 1992 and 2008 were evaluated for racial/ethnic differences in risk for six common cancers after transplantation. Compared to white recipients, black recipients had lower incidence of non-Hodgkin lymphoma (NHL) (adjusted incidence rate ratio [aIRR] 0.60, p<0.001) and higher incidence of kidney (aIRR 2.09, p<0.001) and prostate cancer (aIRR 2.14, p<0.001); Hispanic recipients had lower incidence of NHL (aIRR 0.64, p = 0.001), lung (aIRR 0.41, p < 0.001), breast (aIRR 0.53, p = 0.003) and prostate cancer (aIRR 0.72, p = 0.05). Colorectal cancer incidence was similar across groups. Standardized incidence ratios (SIRs) measured the effect of transplantation on cancer risk and were similar for most cancers (p≥0.1). However, black and Hispanic recipients had larger increases in kidney cancer risk with transplantation (SIRs: 8.96 in blacks, 5.95 in Hispanics vs. 4.44 in whites), and only blacks had elevated prostate cancer risk following transplantation (SIR: 1.21). Racial/ethnic differences in cancer risk after transplantation mirror general population patterns, except for kidney and prostate cancers where differences reflect the effects of end-stage renal disease or transplantation. Among US kidney recipients, cancer incidence varies by race/ethnicity, reflecting both background differences in the general population and, for some cancers, differing effects of transplantation on risk.