New ANZDATA registry data challenge the blanket practice of delaying kidney transplantation for years after a cancer diagnosis, suggesting some patients could be considered earlier.
A study published in the American Journal of Kidney Diseases [link here] found outcomes varied markedly by cancer type, stage and patient age, arguing against a one-size-fits-all approach.
The research drew on data from 3,052 patients receiving haemodialysis or peritoneal dialysis in Australia and New Zealand between January 2000 and December 2021, all subsequently diagnosed with cancer (excluding keratinocyte cancers). Mean follow-up was 1.3 years.
The most common cancers were lung, colorectal, prostate, liver (including intrahepatic bile duct) and kidney
Most patients presented with localised or regional disease.
Of the cohort, 1,245 died from cancer, 1,127 from other causes, and 204 went on to receive a kidney transplant. Over a median post-transplant follow-up of 5.3 years, 16 died from cancer and 35 from other causes.
The crossover finding
The study’s key finding was a “crossover point”, the moment when the risk of cancer-related death fell below the risk of dying from something else. For localised or regional prostate, kidney and colorectal cancers, this crossover typically occurred within the first year after diagnosis, substantially earlier than traditional transplant eligibility guidelines suggest.
Patients with these cancers had a higher likelihood of dying from other causes than from cancer, regardless of age.
The investigators, led by Dr Ryan Gately from Brisbane’s Princess Alexandra Hospital, cautioned that the crossover points “should not be taken as definitive evidence that transplantation is safe or appropriate thereafter,” noting that the absolute risk of cancer-related death may remain unacceptably high, and that immunosuppression raises the probability of cancer recurrence or de novo malignancy.
Cancer-related death was the predominant outcome in patients with distant metastases, particularly in liver and lung cancers, likely reflecting the aggressiveness of advanced disease and limited treatment options in dialysis patients.
Even among younger patients with localised or regional lung or liver cancers, the study found that cancer-related death tended to occur early. Although the hazard declined over time, it remained comparable to the hazard of death from other causes, with only minimal separation in risks after an observed crossover around two years, suggesting late recurrence remained possible and a more extended observation period was appropriate before considering transplantation.
The bottom line
Mortality from non-cancer causes exceeded cancer-related mortality across all age groups in transplant recipients with a prior cancer diagnosis.
The authors concluded that patients under 70 with localised or regional prostate, kidney or colorectal cancer could reasonably be considered for transplant earlier than current guideline-mandated waiting periods suggested.
They called for future research incorporating treatment response, molecular and genetic data, and patient-reported outcomes to refine risk stratification further.