Conversion to sirolimus in posttransplant renal neoplasms

Area of Science:

• Nephrology
• Oncology
• Immunology

Background:

• Calcineurin inhibitors (CNIs) are linked to posttransplant malignancies like lymphoma and solid organ tumors.
• Sirolimus (SRL) demonstrates anti-tumor properties in vitro and in vivo, and is effective for Kaposi's sarcoma.
• Conversion to SRL may benefit transplant patients with tumors who are on CNIs.

Purpose of the Study:

• To evaluate the impact of converting from CNI-based immunosuppression to SRL in organ transplant patients who developed tumors.
• To analyze tumor evolution, renal function, and adverse effects following SRL conversion.

Main Methods:

• 25 patients with tumors were switched from CNIs to SRL between December 2001 and May 2006.
• Tumor progression, renal function (creatinine clearance, proteinuria), and adverse events were monitored.
• Mean follow-up was 19 months.

Main Results:

• Tumor progression stabilized in 76% of patients.
• Creatinine clearance showed a non-significant increase; proteinuria significantly increased (P=.004).
• Adverse events included anemia, thrombocytopenia, oral ulcers, skin rash, GI issues, and edema. Improved blood pressure was noted in 16%.

Conclusions:

• Conversion to SRL stabilized tumor progression in most renal transplant patients with neoplasms.
• Renal function generally improved, despite increased cholesterol and proteinuria.
• SRL conversion is a viable strategy for managing post-transplant malignancies.