Survival after a cancer diagnosis among solid organ transplant recipients in the United States

Abstract

BACKGROUND: Transplant recipients have an elevated risk of cancer because of immunosuppressive medications used to prevent organ rejection, but to the authors' knowledge no study to date has comprehensively examined associations between transplantation status and mortality after a cancer diagnosis. METHODS: The authors assessed cases in the US general population (N=7,147,476) for 16 different cancer types as ascertained from 11 cancer registries. The presence of a solid organ transplant prior to diagnosis (N=11,416 cancer cases) was identified through linkage with the national transplantation registry . Cox models were used to examine the association between transplantation status and cancer-specific mortality, adjusting for demographic characteristics and cancer stage. RESULTS: For the majority of cancers, cancer-specific mortality was higher in transplant recipients compared with other patients with cancer. The increase was particularly pronounced for melanoma (adjusted hazard ratio [aHR], 2.59; 95% confidence interval [95% CI], 2.18-3.00) and cancers of the breast (aHR, 1.88; 95% CI, 1.61-2.19), bladder (aHR, 1.85; 95% CI, 1.58-2.17), and colorectum (aHR, 1.77; 95% CI, 1.60-1.96), but it also was increased for cancers of the oral cavity/pharynx, stomach, pancreas, kidney, and lung as well as diffuse large B-cell lymphoma (aHR range, 1.21-1.47). Associations remained significant after adjustment for first-course cancer treatment and generally were stronger among patients with local-stage cancers for whom potentially curative treatment was provided, including patients with melanoma (aHR, 3.82; 95% CI, 2.94-4.97) and cancers of the colorectum (aHR, 2.77; 95% CI, 2.07-3.70), breast (aHR, 2.08; 95% CI, 1.50-2.88), and prostate (aHR, 1.60; 95% CI, 1.12-2.29), despite the lack of an association for prostate cancer overall. CONCLUSIONS: For multiple cancer types, transplant recipients with cancer appear to have an elevated risk of dying of their cancer, even after adjustment for stage and treatment, which may be due to impaired immunity. Cancer 2019;125:933-942.

Elevated incidence of head and neck cancer in solid organ transplant recipients

“…Prior studies have demonstrated increased rates of cancer‐related mortality in solid organ transplant recipients, as would be expected, including for head and neck cancers, but again most studies have been hampered by the lack of a control group, making survival comparisons difficult . However, two recent studies have utilized cancer databases to compare cancer patients with transplants to those without: each found a higher rate of cancer‐specific mortality for transplant recipient with certain head and neck cancers . The largest study found increased cancer‐specific mortality in oral cavity/pharynx, but not for thyroid; in the present study, we found significantly worse survival in thyroid patients, but we assessed OS, not cancer‐specific mortality, making comparison of findings challenging .…”

“…Additionally, as previous studies have primarily assessed only transplant patients without comparators, the effects of solid organ transplant on head and neck cancer survival is uncertain. A few studies have demonstrated that transplant patients with cancer have worse survival compared with other cancer patients, but research is limited …”

Survival among solid organ transplant recipients diagnosed with cancer compared to nontransplanted cancer patients—A nationwide study

“…In a recent study by D'Arcy et al ., with similar design to ours, 7,147,476 cancer cases (of which 11,416 among OTRs) diagnosed 1987–2014 were identified from 11 US cancer registries and followed for cancer‐specific mortality. Comparing rates of cancer‐specific death among OTRs and non‐OTRs, the authors found significantly elevated HRs for melanoma, high‐grade lymphoma, breast, colorectal and bladder cancer, in line with our results.…”

Cancer mortality in kidney transplant recipients: An Australian and New Zealand population‐based cohort study, 1980–2013

“…Poorer survival has been attributed to inhibition of the immune response to melanoma due to immunosuppression and may suggest treatment algorithms developed for the general population may not be effective in transplant recipients. Transplant recipients in the US with melanomas are also less likely to undertake surgery, radiotherapy or chemotherapy compared to the general population . Whether this is the case for Australian and New Zealand given differences in healthcare systems, needs further investigation.…”