A 41-year-old man was admitted to our hospital 567 days after a double UCBT for B-ALL with t(1; 19). His treatment history in brief is as follows. After cycle 3A of Hyper-CVAD, he developed symptoms concerning relapse. A bone marrow biopsy confirmed B-ALL. His regimen was changed to Augmented Hyper-CVAD. A repeat bone marrow biopsy was negative for disease.
Given his relapse during treatment, the patient was referred for bone marrow transplant (BMT) evaluation. He was HLA typed and had neither a sibling nor a suitable volunteer unrelated donor match. Thus, he underwent a double UCBT. He received reduced-intensity conditioning prior to his UCBT with cyclophosphamide 50 mg/kg, fludarabine 200 mg/m2, and 200 cGy TBI (Cy/Flu/TBI). GVHD prophylaxis included CSA and MMF. After transplant, bone marrow (BM) and peripheral blood (PB) chimerism was 100% donor.
His posttransplant course was complicated by graft-versus-host-disease (GVHD) of skin and the gastrointestinal tract. The GVHD was managed with a brief course of steroids and cyclosporine. Bone marrow and peripheral blood chimerism was 100% donor.
At approximately day 515 after transplant he was noted to be thrombocytopenic and 8% blasts were reported on peripheral blood. A bone marrow biopsy was performed, which revealed a donor derived acute myeloid leukemia (AML), with 22% blasts showing an immature myeloid phenotype by flow cytometry (CD13+, CD34+, HLA-DR+, CD4dim+, CD64dim+, and CD33 partial dim+), negative for CD10 and CD19, both of which had been expressed in the prior B-ALL. His peripheral blood and bone marrow chimerism remained 100% donor. FISH was negative for t(1; 19). He received 1 cycle of decitabine at 20 mg/m2 for 10 days and responded well to the treatment. A bone marrow biopsy performed 8 weeks after the completion of the cycle revealed no evidence of AML. Additional cycles of treatments were held secondary to infectious complications.
He was readmitted to the hospital on day 567 after transplant with fever, cough, pleuritic chest pain, and tachycardia. A chest X-ray showed small pleural effusions. He was noted to have EKG changes with T-wave inversions in leads V3-V5 (Figure 1). He had both an elevated troponin at 1.8 ng/mL and an elevated brain natriuretic protein at 805 pg/mL. An echocardiogram demonstrated pericardial effusion and thickened pericardium and could not rule out a restrictive process. A cardiac catheterization showed no significant pathology. A high resolution CT scan of the chest revealed small circumferential pericardial and nodular soft tissue densities posterior to the heart, considered suspicious for metastatic deposits (Figure 2). He ultimately underwent a pericardiectomy.
Histopathological evaluation revealed an infiltrate of atypical cells, seen in sheets and clusters throughout the pericardium and focally within adjoining adipose tissue. By immunohistochemistry, the atypical cells showed an immature myeloid/monocytic immunophenotype: CD34 focal+, CD43+, MPO focal+, CD117 focal+, CD68 weak+, CD163 focal+, PAX5-, CD56-, TdT-, and CD79a focal weak+ (Figure 3).
Chimerism studies of the biopsied tissue revealed that the lesion was entirely donor derived. A bone marrow biopsy showed normal hematopoiesis with full donor chimerism. Thus cardiac myeloid sarcoma represented an isolated site of disease.
Unfortunately, the patient continued to clinically deteriorate. He developed multiorgan failure requiring vasopressor support, hemodialysis, and an intra-aortic balloon pump. He expired on day 579 after transplant.
The umbilical cord blood registry was contacted and the donor was reported to be in good health with no evidence of leukemia.