De novo thyroid cancer following solid organ transplantation—A 25‐year experience at a high‐volume institution with a review of the literature

Abstract

Rate of thyroid cancer is not significantly higher in patients who underwent solid organ transplantation compared to general population. Stage at presentation and prognosis also appear to be similar to that of the general population. Post-transplant screening for thyroid cancer remains debatable; however, when thyroid cancer is discovered, treatment should be similar to that of non-transplant patients. J. Surg. Oncol. 2017;115:105-108. © 2017 Wiley Periodicals, Inc.

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

“…Salivary gland tumors have previously been linked to history of transplant, so our findings agree with prior research . Thyroid cancers have also previously been shown to be increased in transplant patients . Interestingly, though immunosuppression has been hypothesized to be the driver of most cancer formation in transplant recipients (particularly virus‐associated cancers, as previously discussed), thyroid cancers may not follow this pattern .…”

“…One recent large study of thyroid risk found an SIR of 2.5, and noted that the high rate of thyroid cancers may be partially due to surveillance bias; however, the same study found an increased rate of larger and higher stage thyroid cancers, which are less likely than smaller, low stage tumors to be affected by surveillance bias . Additionally, prior estimates of thyroid cancer risk in transplant recipients have been wide‐ranging, which may be because thyroid cancer rates have increased in the general population over time, making comparisons between longitudinal cohorts and population risk estimates more problematic . Thus, our estimation of an RR of 1.9 for thyroid cancer in transplant patients may be more accurate than prior estimates that suggested SIRs of as high as 6.9 or 7.0 …”

“…The most common posttransplant malignancies include skin cancers, lymphoproliferative disorders, and lung cancer . Several studies have also demonstrated increased risk of head and neck cancers; in particular, oral cavity, oropharynx, and thyroid cancers have been shown to be associated with prior solid organ transplant . While kidneys are the most commonly transplanted—and correspondingly, studied—solid organ, an increased rate of head and neck cancers has also been shown in heart, lung, and liver transplantations …”

Reassessing risks and benefits of living kidney donors with a history of thyroid cancer

“…Even if transplant recipients were to develop de novo papillary thyroid cancer, their risk of death would be much greater from end‐stage renal disease (approximately a 60% 5‐year survival on dialysis) than from papillary thyroid cancer. Unlike many other cancers, papillary thyroid cancer does not appear to progress more rapidly post‐transplant, nor does it occur at a more advanced stage . Direct metastasis to the transplanted kidney from solid malignancies is exceedingly rare …”

Solid organ transplant and thyroid cancer

“…Kouter and Duh from UCSF have reviewed their experience of thyroid cancer, occurrence, stage, management and prognosis in individuals who have undergone solid organ transplantation at their institution . Clearly, they have a large series of patients having undergone solid organ transplant surgery including kidney, liver, and pancreas.…”