Severe combined immunodeficiency (SCID) is a defect in the differentiation and function of T cells. An increased malignancy risk, mainly lymphatic malignancy, has been described in patients with SCID. We report a patient with X-linked SCID who developed acute myeloid leukemia, derived from the recipient with somatic NRAS mutation 4 months after cord blood transplantation (CBT). Loss of heterozygosity phenomenon of the recipient at 6q14 locus was observed at 2 months post-CBT and progressed to 6q deletion (6q−) chromosome abnormality. Somatic NRAS mutation was detected at 3 months post-CBT. Thus, 6q− and NRAS mutation were strongly associated with the leukemic transformation in our patient.
*Department of Pediatrics, Shinshu University School of Medicine
†Department of Laboratory Medicine, Shinshu University Hospital
‡Department of Infection and Host Defense, Graduate School of Medicine, Shinshu University, Matsumoto, Japan
T.S. and M.M. contributed equally.
The authors declare no conflict of interest.
Reprints: Yozo Nakazawa, MD, PhD, Department of Pediatrics, Shinshu University School of Medicine, 3-1-1, Asahi, Matsumoto 390-8621, Japan (e-mail: email@example.com).
Received December 13, 2016
Accepted May 22, 2017