Renal cell carcinoma of native kidney in renal transplant recipients.

Objective: To evaluate the prevalence, prognosis and possible risk factors of renal cell carcinoma (RCC) of the native kidney in renal transplant recipients.

Patients And Methods: We retrospectively re-examined the follow-up data of 373 consecutive renal transplant recipients at our institution between August 1993 and September 2004. We collected the data of all de novo RCC of the native kidney in the current analysis.

Results: Of the 373 patients examined, 12 tumours of the native kidney were diagnosed in 10 individuals. The mean ages at transplantation and diagnosis were 33 and 45.8 years, respectively. Thirteen malignancies were discovered fortuitously. Among the renal ultrasonograms there were two false-negative results. The mean tumour size was 21 mm. Nephrectomy was performed in all cases. Among the 12 kidney malignancies, there were five conventional RCCs and seven papillary RCCs. Half of all tumours were Furhman Grade 3 lesions, and pT1aN0M0 tumours also accounted for all malignancies in the current cohort. One of the 10 patients died, from progression of metastases 6 years after diagnosis. One patient had a local recurrence 2 years after diagnosis. The other eight patients were alive with no evidence of disease at the time of the current report. No significant relationship was detected between RCC occurrence and clinical patient characteristics.

Conclusions: There appears to be a greater risk of RCC of the native kidney in patients with end-stage renal disease. The present results suggest that an annual examination of the native kidney before and after renal transplantation is essential.