2019 Volume 65 Issue 4 Pages 751-753
A 66-year-old male was diagnosed with polycythemia vera (PV) in September 200X. Although exsanguination was regularly performed, acute myelogenous leukemia was detected in November 200X+3. Following complete remission, non-myeloablative bone marrow transplantation from an HLA-matched sibling donor was conducted in February 200X+4. The ABO blood group was determined to be a major-minor mismatch. Engraftment was achieved on Day 20. Although acute GVHD was confirmed to be a maximum of grade 2, systemic treatment was not required. The stage of chronic GVHD was also confirmed to be limited. Blood-type transition to the donor's blood type was confirmed on Day 577. Immunosuppressive therapy was discontinued on Day 628. On Day 1,697, blood group typing was incidentally performed and demonstrated heterogeneous blood groups. Bone marrow puncture was performed on the same day. While there was no recurrent tumor, the sample was a mixed chimera consisting of 79.6% of cells from the recipient and 19.6% of cells from the donor. Rejection was noted on Day 1,931. However, there has been no relapse, and the patient has remained negative for the JAK2 gene mutation. While it is difficult to detect relapse-free rejection in patients with long-term remission after transplantation, follow-up involving blood-group investigation may be necessary.
