G WONG1, WH LIM2
1Centre for Kidney Research & Department of Renal Medicine, Westmead Hospital, Sydney; 2 Department of Renal Medicine, Sir Charles Gairdner Hospital, Perth
Aim: We aimed to estimate the risk of graft loss and death in kidney transplant recipients with and without incident cancer, and to determine the cancer stage at diagnoses in those who have developed incident cancer.
Background: The excess risk for cancer in kidney transplant recipients is substantial, but the allograft and patient survivals after cancer development are under-studied.
Methods: This is a population-based cohort study of all primary live and deceased donor kidney transplant recipients in Australia and New Zealand between 1990-2012. The risks of overall graft loss, death with a functioning graft (DWFG) and all cause mortality in kidney transplant recipients with and without incident cancer were determined using Cox regression analysis. Types and cancer stage at diagnoses were reported.
Results: Of 12,545 transplant recipients followed for a median of 6.9 years (91,380 patient-years), 1184 (9.4%) developed incident cancers. Digestive and kidney/urinary tract cancers were the most common cancers, although digestive and respiratory tract cancers were more aggressive, with 40% reported as advanced cancers at time of cancer diagnosis. Compared with recipients with no prior cancer, the adjusted hazard ratios (HR) of recipients with incident cancers were 1.39 (95%CI 1.25-1.44) for overall graft loss, and 2.92 (95%CI 2.56-3.33) for DWFG. For all-cause mortality, the adjusted HR of recipients with incident cancers was 1.95 (95%CI 1.73-2.19), with over 80% of deaths attributed to cancer.
Conclusions: Incident cancer after kidney transplantation is a significant risk factor for DWFG and all-cause mortality, with the majority of deaths attributed to cancer. A greater understanding of the barriers to screening and treatment approaches following cancer diagnosis may lead to improve survival in kidney transplant recipients with cancer.