Changes in cancer incidence and outcomes among kidney transplant recipients in the United States over a thirty-year period

Abstract

Recipients of kidney transplants have elevated cancer risk compared with the general population. Improvements over time in transplant care and cancer treatment may have affected incidence and outcomes of cancer among recipients of kidney transplant. To evaluate this, we used linked United States transplant and cancer registry data to study 101,014 adult recipients of kidney transplants over three decades (1987-1996, 1997-2006, 2007-2016). Poisson regression was used to assess trends in incidence for cancer overall and seven common cancers. Associations of cancer with risk of death-censored graft failure (DCGF) and death with functioning graft (DWFG) were evaluated with Cox regression. We also estimated absolute risks of DCGF and graft failure following cancer for recipients transplanted in 2007-2016. There was no significant change in the incidence of cancer overall or for six common cancers in recipients across the 1987-2016 period. Only the incidence of prostate cancer significantly decreased across this period after multivariate adjustment. Among recipients of kidney transplants with non-Hodgkin lymphoma, there were significant declines over time in elevated risks for DCGF and DWFG but no significant changes for other combined cancers. For recipients transplanted in the most recent period (2007-2016), risks following cancer diagnosis remained high, with 38% experiencing DWFG and 14% graft failure within four years of diagnosis. Absolute risk of DWFG was especially high following lung cancer (78%), non-Hodgkin lymphoma (38%), melanoma (35%), and colorectal cancer (49%). Thus, across a 30-year period in the United States, there was no overall change in cancer incidence among recipients of kidney transplants. Despite improvements for non-Hodgkin lymphoma, cancer remains a major cause of morbidity and mortality.

Keywords: cancer; graft failure; incidence; kidney transplant; mortality.

Figure 1. Cumulative incidence of DWFG and graft failure following a cancer diagnosis among KTRs transplanted in 2007–2016.

Cumulative incidence was estimated using competing risk methods. Results are shown for graft failure and death with functioning graft (DWFG) as stacked regions. The proportion of KTRs with each event at four years after transplantation are presented below each panel. Abbreviations: DWFG death with functioning graft, GF graft failure, NHL non-Hodgkin lymphoma.