Papillary microcarcinoma of the thyroid gland in renal transplant patients

THYROID DISORDERS PREVALENCE IN A COHORT OF KIDNEY TRANSPLANT RECIPIENTS

Context

As the life expectancy prolongs, malignancy has become an important issue in renal transplant recipients (RTRs). Thyroid cancer is the most common endocrine malignancy with ongoing increase in incidence all over the world.

Objective and design

This is a cross-sectional study that investigates the thyroid disorders and the prevalence of thyroid nodule and cancer in RTRs.

Subjects and methods

204 RTRs were evaluated for the thyroid diseases with ultrasonography, serum thyroid stimulating hormone, free T4, free T3 levels, anti-thyroglobulin antibody and anti-thyroid peroxidase antibody levels; FNAB was carried if required.

Results

191 patients (94.1%) had normal thyroid function. Subclinical hypothyroidism was diagnosed in 11 patients, subclinical hyperthyroidism in 1 patient and low T3 syndrome in 4 patients. The FNAB was performed in 17 (27.9%) from 61 patients with thyroid nodule. The cytological examination of biopsy materials revealed that 2 (11.8%) nodules were suspicious for malignancy, 13 (76.5%) were benign, and 2 (11.8%) with non diagnostic cytology. Thyroid cancer prevalence was 0.2% in Turkey but we detected that 0.98% of RTRs had thyroid cancer.

Conclusions

Screening the RTRs for thyroid disorders is necessary, so that early diagnosis and appropriate treatment of thyroid disease and cancer may improve the quality of life.

Incidence of thyroid dysfunction and thyroid cancer in renal transplant recipients: a single center experience

BACKGROUND

The prevalence of thyroid cancer in renal transplant population has not been widely studied, and there is no consensus on the management of thyroid cancer in transplant patients. The aim of this study was to evaluate changes in thyroid hormone levels and investigate the incidence of the thyroid cancer after renal transplantation.

MATERIALS AND METHODS

From October 1989 to April 2007, 122 renal allograft recipients that were being followed underwent thyroid ultrasonography to determine nodules together with thyroid hormone levels. Ultrasound-guided fine-needle aspiration biopsy (FNAB) was performed to the nodules > 10 mm or those with 8-10 mm diameter but with calcifications.

RESULTS

One hundred and eight patients (88.5%) had normal thyroid function. None of the patients had overt hypothyroidism, 2 had subclinical hypothyroidism, 10 subclinical thyrotoxicosis, and 2 low T3 syndrome. Mean thyroid volume was 14.2 +/- 7.2 ml. In all, 91.8% was diagnosed with goiter (n = 112). Seventy-two thyroid nodules were detected in 49 kidney allograft recipients (single nodule in 30, multiple in 19 patients). Eighty-four biopsy samples were reported as benign (n = 21, 87.5%), 8 as suspicious (n = 2, 8.3%), and 4 as inadequate (n = 1, 4.1%). After surgery, one of the patients (0.8%) with suspicious FNAB was reported as papillary thyroid carcinoma.

CONCLUSION

Because of the high incidence of thyroid dysfunction in transplant patients, screening of thyroid function should be a part of follow-up. Our results suggest that although frequency of nodules is increased in kidney transplant patients, prevalence of thyroid cancer is slightly, but not significantly, higher than that of the normal population.

De novo malignant melanoma occurred in renal allograft: DNA typing to determine the origin of the tumour

Malignant diseases are considered as great challenges in clinical transplantation. It is well known that the incidence of malignancy is higher in the transplanted population if compared with the normal population. It is important to distinguish between neoplastic diseases originating from pre-existing lesions in the transplanted organs and de novo graft tumours. Post-transplant malignancy of donor origin is a rare complication of organ transplantation, most likely transmitted as micrometastases within the parenchyma of the donor organ or from circulating tumour cells contained within the organ. Malignant melanoma, although its incidence is rather low, is one of the most common donor-derived tumour inadvertently transplanted, comprising 28% of donor transmitted tumours. Malignant melanoma in the graft without dermatological localisation is extremely rare. We report a case of de novo melanoma occurring in the allograft, where transmission from the donor was excluded by DNA (desoxyribonucleic acid) investigation. We did not find any data in the literature where a malignant melanoma occurred after transplantation in the transplanted kidney without any skin lesions and the donor origin was excluded. We draw attention to the importance of the DNA typing in case of tumours occurring in immunosuppressed patients.

Incidence and clinical behavior of papillary thyroid carcinoma in renal allograft recipients: a single center experience

The chronic use of immunosuppressive therapy in transplant recipients increases the long-term risk for carcinoma. However, there is insufficient knowledge regarding the incidence and biological behavior of papillary thyroid carcinomas (PTC) in renal allograft recipients. In the present study we examined the incidence and biological behavior of PTCs among 1739 patients transplanted between January 1986 and December 1999 who had been followed for a mean period of 137 months (range, 84-238 months). During the follow-up, 129 (7.4%) recipients were identified to display posttransplantation malignancies, including 12 (0.7%) with PTCs. The 6 male and 6 female patients had a mean age of 41 years (range, 23-57 years). Nine cases (incidentalomas) were diagnosed based on ultrasonographic (US) screening. Eight of those 9 were TNM stage I, 2 of the 3 clinical carcinomas were TNM stage IVa. During a mean follow-up of 94 months (range, 18-159 months), 2 (16.7%) PTC patients developed locoregional recurrence, but no patients showed distant metastases. These data showed that recipients had a higher incidence of PTC compared with the general Korean population (0.7% vs 0.02%). Posttransplantation PTC tended to show no difference in gender distribution, and was often associated with aggressive lymphatic metastasis. However, most incidentalomas showed favorable treatment outcomes. In conclusion, routine surveillance of the thyroid gland using US screening is recommended to ensure early detection, treatment, and favorable prognosis of PTC.

THYROID CANCER IN THE RENAL TRANSPLANT POPULATION: EPIDEMIOLOGICAL STUDY

BACKGROUND

The epidemiology of thyroid neoplasms in the renal transplant population has not been widely published. The present study compares the behaviour of thyroid cancer in the transplant cohort with that of the general population. It also documents the transplantation outcomes of patients with thyroid and non-thyroid cancers.

METHODS

All recipients of renal grafts are registered with the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry. Data were obtained from this institution and analysed using Microsoft Excel and Stata statistical software. Risk ratio, attributable risk, Mann-Whitney test, and the Kaplan-Meier survival probability were calculated.

RESULTS

Between 1963 and 31 March 2002, 23 (0.22%) patients were diagnosed with thyroid cancer from a cohort of 10,689 renal transplant recipients. The median age in the renal-transplant thyroid cancer group was 48.2 years (range: 23-67 years), and there were 11 (48%) male patients, compared to 26% of thyroid cancer patients in the general population (P = 0.02). The median time to thyroid cancer diagnosis after transplantation was 68 months (range: 3-253 months) compared to 102 months (range: 3-363 months; P = 0.004) in non-thyroid cancers. Ten patients (43%) were found to have lymphatic metastasis, eight of whom presented at the time of primary diagnosis. The risk ratio (RR) was 5.2 (95% confidence interval: 2.0-16.6), with an attributable risk of 17.4 cases per 10,000. There were two cancer-related deaths resulting in a survival probability of 89% at 5, 10 and 15 years.

CONCLUSIONS

There is a higher incidence of thyroid cancer and an altered sex distribution in the renal transplant population. A significant proportion presents with lymphatic metastasis requiring lymph node dissection and radioactive iodine treatment.

Early de novo malignancies after kidney transplantation

INTRODUCTION

Immunosuppressed renal transplant patients display a higher incidence of carcinoma than the general population. The chronic use of immunosuppressive therapy to prevent acute rejection increases the long-term risk of cancer. We reviewed our experience to identify factors affecting the development of de novo neoplasms.

PATIENTS AND METHODS

Between January 2000 and May 2003, 135 renal and three combined kidney-pancreas transplantations were performed.

RESULTS

Sixteen (11.6%) cancers were diagnosed in nine renal transplant recipients (6.5%). Tumors presented at a mean time of 14 months. Three patients displayed in malignancies; three, Kaposi's sarcoma; one, papillary microcarcinoma of the thyroid; one, bladder carcinoma; and one, breast carcinoma.

CONCLUSION

Although de novo malignancies occur more frequently many years after kidney transplantation, our experience demonstrates that they can occur early during the posttransplant follow-up. Skin malignancies showed the best prognosis, probably because of early detection and treatment. Patients with Kaposi's sarcoma benefit from reduction or cessation of immunosuppression, but this entails a higher risk of graft loss. Solid organ de novo malignancies are often more aggressive than those in normal population; the life expectancy of these recipients is low.