Donor-derived second hematologic malignancies after cord blood transplantation

Area of Science:

• Hematology
• Oncology
• Transplant Immunology

Background:

• Double umbilical cord blood transplantation (UCBT) is a viable option for adult patients lacking a matched donor.
• The long-term risk of secondary malignancies following UCBT remains largely uncharacterized.

Purpose of the Study:

• To investigate the incidence and characteristics of second malignancies after double UCBT in adult patients with hematologic malignancies.

Main Methods:

• A cohort of 98 adult patients undergoing double UCBT was analyzed.
• Patients received either reduced-intensity conditioning (RIC) or myeloablative conditioning (MAC) regimens.
• Graft-versus-host disease (GVHD) prophylaxis strategies included sirolimus-based or non-sirolimus-based regimens.

Main Results:

• Eighteen patients (18.4%) developed a second malignancy, with a median onset of 134 days post-transplant.
• Lymphoma (16 cases) and myelodysplastic/myeloproliferative disorders (MDS/MPD, 2 cases) were the most common second malignancies.
• Sixteen of the second malignancies were confirmed as donor-derived, including both MDS/MPD cases and 14 lymphomas.

Conclusions:

• Donor-derived second malignancies, specifically myelodysplastic syndromes, can occur following double UCBT.
• No association was found between GVHD prophylaxis, HLA matching, primary disease, age, or cell dose and the rate of second malignancy.
• Investigating donor origin is crucial for patients with suspected relapse after double UCBT.