Editorial comment to A case of recurrence of renal cell carcinoma after simultaneous radical nephrectomy and cadaver renal transplant.

Malignancy is among the primary causes of mortality in renal transplant recipients. The risk of new malignancies in renal transplant recipients is 2–3 times higher than in the general population. If a possible recipient has a cancer history, a waiting period before renal transplantation is often required after cancer treatment. Immunosuppression after renal transplantation might not affect the prognosis of low‐risk renal cell carcinomas. Posttransplant malignancies, which can occur de novo or as cancer recurrences, result from chronic exposure to immunosuppressive drugs and are often more aggressive than those that develop in the nontransplant setting. Malignancy after renal transplantation requires cautious and long‐term follow‐up.

Inoue et al. reported a case of renal cell carcinoma recurrence in a patient who received simultaneous treatment with radical nephrectomy for a left renal tumor and cadaver renal transplantation. The tumor was a clear cell carcinoma (G2, pT1b). Twelve years after renal transplantation, an anterior mediastinal mass and lung and bilateral adrenal metastases were observed. Noteworthy points of this case are the association between immunosuppressive drugs and recurrence and the effect of simultaneous treatment with radical nephrectomy and renal transplantation on tumor control in patients with renal cancer.

Mammalian target of rapamycin (mTOR) inhibitors have immunosuppressive and antitumor effects. Treatment conversion to mTOR inhibitors is correlated with a low incidence of malignancies and is safe for renal function and graft survival in patients with a cancer history. The use of immune checkpoint inhibitors is another treatment option for renal cancer. However, it might be associated with a high risk of acute rejection. Renal transplantation might not be correlated with a high risk of recurrence compared with dialysis in patients with low‐risk renal cancer. Nevertheless, recurrence of malignancy after renal transplantation requires cautious and long‐term follow‐up. Expectantly, considering the various risks in renal transplant recipients, optimal treatment regimens with immunosuppressive drugs and standard doses will be determined in the future.

Conflict of interest

The author declares no conflict of interest.