Conversion to rapamycin immunosuppression for malignancy after kidney transplantation: case reports

Area of Science:

• Nephrology
• Oncology
• Immunology

Background:

• Malignancies are a significant cause of morbidity and mortality in renal transplant recipients due to immunosuppressive therapy.
• Rapamycin demonstrates potential in limiting the proliferation of various malignant cell lines both in vivo and in vitro.

Observation:

• Eight kidney transplant recipients developed malignancies including metastatic gastric cancer, colon cancer, bilateral nephrourothelioma, skin cancer, Kaposi's sarcoma, and post-transplant lymphoproliferative disorder (PTLD).
• Following malignancy diagnosis, patients transitioned from calcineurin inhibitor-based immunosuppression to rapamycin, often in combination with steroids or mycophenolate mofetil.

Findings:

• Two patients with metastatic cancer did not survive chemotherapy.
• The remaining six patients, treated with rapamycin-based immunosuppression, achieved cancer remission with stable renal graft function after a mean follow-up of 20.3 months.
• Tumor regression was observed in patients with nonmetastatic tumors.

Implications:

• Rapamycin-based immunosuppression may offer a therapeutic option for managing nonmetastatic tumors in renal transplant recipients.
• The study highlights the need to differentiate the effects of rapamycin versus reduced immunosuppression on tumor regression.
• Further research is warranted to elucidate the precise role of rapamycin in post-transplant cancer management.