Recurrent unbalanced whole-arm t(1;10)(q10;p10) in myelodysplastic syndrome: a case report and literature review

Allogeneic Hematopoietic Stem Cell Transplantation for GATA2 Deficiency Using a Busulfan-Based Regimen

Allogeneic hematopoietic stem cell transplantation (HSCT) reverses the bone marrow failure syndrome due to GATA2 deficiency. The intensity of conditioning required to achieve reliable engraftment and prevent relapse remains unclear. Here, we describe the results of a prospective study of HSCT in 22 patients with GATA2 deficiency using a busulfan-based conditioning regimen. The study included 2 matched related donor (MRD) recipients, 13 matched unrelated donor (URD) recipients, and 7 haploidentical related donor (HRD) recipients. MRD and URD recipients received 4 days of busulfan and 4 days of fludarabine. HRD recipients received low-dose cyclophosphamide for 2 days, fludarabine for 5 days, 2 to 3 days of busulfan depending on cytogenetics, and 200 cGy total body irradiation. MRD and URD recipients received tacrolimus and short-course methotrexate for graft-versus-host disease (GVHD) prophylaxis. HRD recipients received high-dose post-transplant cyclophosphamide (PTCy) followed by tacrolimus and mycophenolate mofetil. At a median follow-up of 24 months (range, 9 to 50), 19 of 22 patients were alive with reversal of the disease phenotype and correction of the myelodysplastic syndrome, including eradication of cytogenetic abnormalities. Three patients died: 1 from refractory acute myelogenous leukemia, 1 from GVHD, and 1 from sepsis. There was a 26% incidence of grades III to IV acute GVHD in the MRD and URD groups and no grades III to IV acute GVHD in the HRD cohort. Similarly, there was a 46% incidence of chronic GVHD in the MRD and URD cohorts, whereas only 28% of HRD recipients developed chronic GVHD. Despite excellent overall disease-free survival (86%), GVHD remains a limitation using standard prophylaxis for GVHD. We are currently extending the use of PTCy to the MRD and URD cohorts to reduce GVHD.

Myelodysplastic syndrome in an infant with constitutional pure duplication 1q41-qter

We report on a Japanese female infant as the fourth patient with the constitutional pure duplication 1q41-qter confirmed by chromosomal microarray and as the first who developed myelodysplastic syndrome (MDS) among those with the constitutional 1q duplication. Common clinical features of the constitutional pure duplication 1q41-qter include developmental delay, craniofacial characteristics, foot malformation, hypertrichosis, and respiratory insufficiency. The association between MDS and the duplication of the genes in the 1q41-qter region remains unknown.

A der(1;15)(q10;q10) is a rare nonrandom whole-arm translocation in patients with acute lymphoblastic leukemia

A rare karyotypic event, der(1;15)(q10;q10), which involves the whole long arms of chromosomes 1 and 15, has been reported in patients with various conditions, including acute myelogenous leukemia, myelodysplastic syndrome, polycythemia vera, and multiple myeloma. Only 27 cases of unbalanced der(1;15)(q10;q10) have been documented in the literature as single or complexed chromosomal abnormalities in hematological malignancies. Here, we describe two cases of acute lymphoblastic leukemia with der(1;15)(q10;q10), and review the previous reports. Although more case studies are needed, we suggest that der(1;15)(q10;q10) should be considered a nonrandom chromosomal abnormality in hematological malignancies including both lymphoid and myeloid neoplasms.