Can a person with a primary brain tumor donate a kidney?

Primary Brain Tumors and Kidney Donation

Individuals with primary brain tumors can generally donate kidneys safely, with the exception of those with high-grade malignant tumors who have undergone procedures that compromise the blood-brain barrier. 1

Risk Assessment for Brain Tumor Donors

Low Risk Brain Tumors (Generally Acceptable)

• Low-grade primary CNS malignancies
• Well-contained tumors without blood-brain barrier compromise
• Tumors without prior interventions that increase metastatic risk

High Risk Brain Tumors (Generally Contraindicated)

• Glioblastoma multiforme (Grade IV gliomas) 1
• High-grade malignant tumors with compromised blood-brain barrier due to:
  • Debulking surgery
  • Radiotherapy
  • Ventricular-systemic shunt interventions 1
• Other absolute contraindications (non-CNS): melanoma, choriocarcinoma, lung cancer 1

Evidence Supporting Brain Tumor Donation

Recent evidence suggests the risk of tumor transmission from donors with primary brain tumors is lower than previously thought:

• A UK registry analysis found no tumor transmission in 448 recipients from 177 donors with primary intracranial malignancy, including 23 grade IV gliomas 1
• A 2023 cohort study in England and Scotland found no histological matches of donor brain tumors among 83 post-transplant malignancies in recipients, even from donors with high-grade tumors 2
• The estimated risk of transmission from CNS tumor donors ranges from slightly above 0% to 3% based on retrospective series 3

Decision-Making Algorithm

1. Determine brain tumor characteristics:

   • Tumor grade (low vs high)
   • Tumor histology
   • Prior treatments (surgery, radiation)
   • Presence of blood-brain barrier compromise

2. Risk stratification:

   • Low risk: Low-grade tumors without blood-brain barrier compromise
   • High risk: High-grade tumors (especially glioblastoma) with blood-brain barrier compromise

3. Decision:

   • Low risk: Proceed with donation
   • High risk: Generally avoid donation, but may consider on case-by-case basis with thorough recipient counseling

Important Considerations

• A thorough examination of thoracic and abdominal cavities for metastatic tumor should be performed during organ retrieval 1
• Recipients must be counseled about the small but definite risk of malignancy transmission 1
• The risk of dying while waiting for a kidney transplant may outweigh the minimal risk of tumor transmission when proper protocols are followed 4
• Donor infection risk factor and microbiological assessments should be performed or updated as close to donation time as possible 1

Pitfalls to Avoid

• Failing to assess tumor characteristics thoroughly
• Not considering the integrity of the blood-brain barrier
• Overlooking the donor's treatment history (surgery, radiation, shunts)
• Not counseling recipients about the small but real risk of tumor transmission
• Forgetting to examine thoracic and abdominal cavities for metastases during retrieval

By carefully evaluating the type and characteristics of the primary brain tumor, most donors with CNS tumors can safely donate kidneys, expanding the donor pool while maintaining recipient safety.