Background: The prevalence rate of thyroid cancers in patients with renal failure is variable in different studies. Our aim was to determine the prevalence and clinicopathological characteristics of thyroid cancers in the dialysis population and to evaluate the potential risk factors.
Methods: We performed a retrospective analysis on end-stage renal disease (ESRD) patients on dialysis and thyroidectomized patients without ESRD (2000-2006). Then we compared the data of thyroid cancer patients on dialysis (n = 9) with the data of patients who had histopathologically verified benign thyroid disease on dialysis (n = 23) and with the histopathological data of thyroid cancer patients without ESRD.
Results: Papillary thyroid cancer (PTC) was the only histotype that was found in 9 of 420 (2.1%) ESRD patients on dialysis. Multifocal PTC was found in eight of nine patients; of them, four had follicular variant of PTC (FVPTC). Two patients had lymphatic metastasis at diagnosis. Eight PTCs were classified as tumor-node-metastasis (TNM) stage I and one as stage II. Among the analyzed factors, age (r = 0.374, p = 0.01) and duration of dialysis (r = 0.436, p = 0.007) showed a significant positive correlation with the occurrence of thyroid cancer.
Conclusions: We conclude that the prevalence of thyroid cancer in patients undergoing dialysis was not higher than that in the background population. Age and duration of dialysis showed a significant positive correlation with the occurrence of thyroid cancer in patients on dialysis. Among the histotypes, there may be higher percentage of PTC, FVPTC, and multifocality in dialysis patients. The effect of these characteristics on prognosis of thyroid cancer in dialysis patients is needed to be further evaluated.