Kidney transplant patients with prostate cancer have similar survival

25th October 2021

Kidney transplant patients with prostate cancer should not be excluded because it does not negatively impact on overall survival.

Kidney transplant patients with prostate cancer still achieve the same benefits in terms of overall survival as those without the cancer, according to the results of a retrospective analysis by researchers from the Division of Nephrology, University Hospitals, Ohio, US. End stage kidney disease (ESKD) which requires maintenance with dialysis or a kidney transplant for survival is associated with an increased risk of death. For example, one retrospective analysis of 242 patients with ESKD, observed an annual mortality rate of 7.4%. Nevertheless, other data has found that the mortality risk from ESKD has actually decreased over the last 15 years although some work indicates how ESKD have higher levels of prostate cancer.

Kidney transplant patients have an improved quality of life compared to those continuing with dialysis but there is uncertainty over whether or not the presence of prostate cancer impacts on mortality risk in those either with ESKD or after transplantation. These were the questions to which the Ohio researchers sought answers in the present study. They turned to the US renal data system and included men aged 40 to 79 years of age with ESKD and took the main exposure to be incident prostate cancer which developed after the initiation of dialysis but before a kidney transplant. Since the clinical characteristics of patients with ESKD and prostate cancer might differ to those without prostate cancer, the researchers used propensity matching with a control group of ESKD patients but without prostate cancer and set the outcomes of interest as the time to kidney transplant and death.

Findings

There were 15,554 patients with ESKD and prostate cancer who were matched with controls, the majority of whom (47%) were aged 70 to 79 years with 42% aged 55 to 69 years. Within the matched cohort, 77.6% of patients with prostate cancer died compared to 77.1% of control patients during a mean follow-up of 3.1 years for those with prostate cancer and 3.5 years for controls. The presence of prostate cancer was associated with a 22% lower likelihood of having a kidney transplant (Hazard ratio, HR = 0.78, 95% CI 0.72 – 0.85) and an 11% higher mortality risk (HR = 1.11, 95% CI 1.08 – 1.14) compared to controls.

However when considering kidney transplant patients and using patients without a prostate cancer and no transplant as the reference point, the hazard ratios for the time to death were 0.20 (95% CI 0.18 – 0.21) for transplant patients with prostate cancer and also 0.20 for transplant patients without prostate cancer.

The authors concluded that the presence of prostate cancer in those with ESDK was associated with only a modest increased risk of death but that once these patients had a kidney transplant, the survival benefits were identical to those without cancer. The suggested the these findings indicate that in kidney transplant patients, the presence of prostate cancer should be a barrier to provision of a new kidney.

Citation

Sarabu N et al. Prostate Cancer, Kidney Transplant Wait Time, and Mortality in Maintenance Dialysis Patients: A Cohort Study Using Linked United States Renal Data System Data. Kidney Medicine 2021

Study assesses response to a third COVID vaccination in kidney transplant patients

29th July 2021

Even after a third COVID-19 vaccine dose, only half of kidney transplant patients developed a sufficient antibody response to vaccination.

Among immunocompromised individuals such as kidney transplant patients, a single COVID-19 vaccine dose has been found to elicit a sufficient response in only 17% of individuals. Furthermore, after a second dose, the response only increased to 54%. With evidence of a lower immune response to vaccination, the French National Authority for Health issued a recommendation in April 2021, that immunosuppressed, recent bone marrow transplant, those on dialysis, and patients with autoimmune diseases who did not respond after two doses of a COVID-19 vaccine, should be offered a third dose.

Given the evidence that even among kidney transplant patients who are fully vaccinated, severe COVID-19 can develop, a team from the Department of Nephrology and Transplantation, Strasbourg University Hospital, France, set out to assess the response to a third vaccination among kidney transplant patients who had an inadequate response to a second vaccination dose. The team examined the effect of the mRNA-1273 (Moderna) vaccine and included all kidney transplant patients who had no prior history of infection with COVID-19 and had anti-spike IgG antibody levels less than 50 arbitrary units, one month after administration of the second vaccination dose. They set a minimum antibody titre level of 50 units, so that any responses above this level could be considered as positive.

Findings
A total of 159 kidney transplant recipients with a median age of 57.6 years (61.6% male) and a median time from transplantation of 5.3 years were included in the analysis. After the second dose of vaccine, 59.7% (95) of patients had not generated an antibody response and the remaining patients showed a response below the positivity limit (6.8–49.9 units). The third vaccine dose was administered a median of 51 days after the second dose and the antibody response was then measured approximately 28 days after this third injection. However, at this time-point, only 49% of patients had antibody levels above 50 units. In addition, a response to the third vaccination was much more likely among those who had developed a response to the second dose (81.3% vs 27.4%, p = 0.01, second dose responders vs non-responders). The results also showed how kidney transplant patients prescribed a combination of tacrolimus, mycophenolate and steroids, were much less likely develop a response than those treated with other regimes (35% vs 63%, p = 0.006). No other factors such as sex, years since transplantation, or serum creatinine levels, had an effect on the development of an antibody response.

The authors reported on how despite three vaccination doses, 51% of kidney transplant patients failed to generate a positive antibody response and that this was more likely among those prescribed a triple therapy regime and concluded that kidney transplant patients should be offered a third vaccination dose.

Citation
Benotmane I et al. Antibody Response After a Third Dose of the mRNA-1273 SARS-CoV-2 Vaccine in Kidney Transplant Recipients with Minimal Serologic Response to 2 Doses. JAMA 2021