Abstract: TH-PO1050
Rare Donor-Derived HER2-Mutant Metastatic Adenocarcinoma After Kidney Transplantation
Session Information
- Transplantation: Clinical - Outcomes, Malignancy, and Pathology
October 22, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 2002 Transplantation: Clinical
Authors
- Guevara-Pineda, Daniel, Yale University, New Haven, Connecticut, United States
- Tapia, Luis Andres, Universidad Peruana de Ciencias Aplicadas, Lima District, Lima Region, Peru
- Petrosyan, Nerses, Brown University, Providence, Rhode Island, United States
- Merhi, Basma Omar, Brown University, Providence, Rhode Island, United States
Introduction
Donor-derived metastatic adenocarcinoma after kidney transplantation is rare, aggressive, and diagnostically challenging
Case Description
A 32-year-old woman with ESRD secondary to IgA nephropathy underwent deceased-donor kidney transplantation with alemtuzumab induction followed by tacrolimus, mycophenolate, and prednisone for maintenance immunosuppression. Her post-transplant course was complicated by delayed graft function, Banff IIA rejection and thrombotic microangiopathy treated with thymoglobulin, corticosteroids, and empiric eculizumab.
Two months later, she developed invasive cavitary pulmonary aspergillosis and BK viremia requiring immunosuppression reduction. At six months post-transplant, she presented with severe back pain, and imaging revealed diffuse osseous metastases and innumerable pulmonary nodules. Biopsy demonstrated metastatic adenocarcinoma positive for CK7 and AE1/AE3 with a HER2 mutation. Extensive evaluation failed to identify a primary tumor source. Immunosuppression was tapered, then graft embolization enabled complete withdrawal without nephrectomy. Her course was further complicated by severe infections and respiratory failure, and she ultimately transitioned to comfort-focused care.
Discussion
Donor-derived malignancy is a rare but devastating complication of solid-organ transplantation, occurring in approximately 0.01%–0.05% of cases. Transmission of adenocarcinoma is particularly uncommon and highly aggressive. This case is notable for the early fulminant presentation of metastatic HER2-mutant adenocarcinoma shortly after transplantation and the diagnostic challenge posed by the overlapping invasive aspergillosis and malignancy. Extensive evaluation failed to identify a primary tumor source, while the absence of retained donor tissue limited donor-recipient molecular concordance testing. Profound immunosuppression—including alemtuzumab induction, corticosteroid pulses, calcineurin inhibition, and eculizumab—likely impaired tumor surveillance. Management was complicated by competing risks of infection, rejection, and malignancy progression. This case highlights the diagnostic and therapeutic complexity of donor-derived malignancy in transplant recipients and underscores the importance of maintaining high index of suspicion for malignancy in atypical early post-transplant presentations.